We're listening to the Naked Bible Podcast. To support this podcast, click at nakedbiblepodcast.com and click on the support link in the upper right-hand corner. If you're new to the podcast and Dr. Heiser's approach to the Bible, click on New Start Here at NakedBiblePodcast.com Welcome to the Naked Bible Podcast, episode 103, Moses and the Bronze Serpent. I'm the layman, Trey Strickland, and he's the scholar. Dr. Michael Heiser, hi Mike, how are you doing this week? Pretty good, pretty good. Well good, good. It's been a long week. Yeah, it has.  I did a few Skywatch episodes to promote Unseen Realm and a book that I've alluded to that I'm working on. It was busy, but it was kind of nice to get away and do a little bit of that. People on that end appreciate the podcast. I really enjoyed the last two episodes with the eschatology. So I'm here for no more. Well, I didn't get any hate mail. No, we got lots of positive feedback in the last two episodes. Yeah, no one emailed me to remind me that I was giving up the faith or anything like that. I never know what to expect when I do prophecy because people just, they're just kind of crazy with it. Yeah, they're passionate about it. It's the end times, Mike, it's the end of the world. Right, right. It matters. It's the end of the world. It's kind of a big deal. It's kind of a big deal. Right. Yeah, well, if the Cubs get in the World Series, I'll pay more attention, you know, because that's, like I said, that's the harbinger of the end right there. Well, we're in Numbers 21 by request. Who would have ever thought that people would ask for a podcast episode in the book of Numbers? Well, here we are. That is the chapter Numbers 21, first nine verses of the Moses and the serpent in the wilderness of the bronze serpent episode. And I've, we're doing this because I was asked by two or three people recently and I've had people ask about this in email on, you know, other occasions. So I figured, hey, why not, you know, this is, it's a good for good kind of episode for a topical episode. So why not? Now, in these verses, I'm going to start off and we're going to read the passage. But the first thing we're going to do is sort of talk about why people kind of wonder about this passage. And it's a little, it's a little bit off the beaten path. We're actually going to get into authorship issues here. But it's actually important because I think the episode in the book of Numbers here needs to be framed in a certain, a certain way. And if you frame it in a certain way, it might sort of relieve some of the tension about the content of the passage and why it's sort of controversial and why people wonder about it. But here's the passage. Let's just start in verse one here, I'm reading ESV. When the Canaanite, the king of Arad who lived in the Negev, heard that Israel was coming by the way of Atharim, he fought against Israel and took some of them captive. And Israel vowed to vow to the Lord and said, if you will indeed give this people into my hand, then I will devote their cities to destruction. And the Lord heed the voice of Israel and gave over the Canaanites and they devoted them and their cities to destruction. So the name of the place was called Hormah. And this is related to Harem. This destruction context is a little bit different. It's sort of retaliatory. But again, the same word that we've often talked about here in the podcast and in unseen realm. Verse four continues from Mount Hor they set out by the way to the Red Sea to go around the land of Edom and the people became impatient on the way. And the people spoke against God and against Moses. Why have you brought us up out of Egypt to die in the wilderness for there is no food and no water.  Then the Lord sent fiery serpents among the people and they bit the people so that the many so that many people of Israel died. And the people came to Moses and said we have sinned for we have spoken against the Lord and against you. Pray to the Lord that he take away the serpents from us. So Moses prayed for the people and the Lord said to Moses make a fiery serpent and set it on a pole and everyone who is bitten when he sees it shall live. So Moses made a bronze serpent and set it on a pole. And if a serpent bit anyone, he would look at the bronze serpent and live. So that's the story. It's a short episode. But again, one of the reasons why people kind of wonder about it is the way this gets referenced in the New Testament with Jesus about the son of man must be lifted up as Moses lifted up the serpent in the wilderness and so on and so forth. So that creates kind of a conundrum in the minds of a number of people. Well, just to start off here, I think we need to think about our own preconceptions here and kind of examine a little bit why this particular episode kind of gets the attention it does. And as I just noted, a lot of Christians find the passage confusing, maybe even troubling. Not only because Jesus references this episode, they wonder what the world's going on with that, you know, why would you reference that? And you ask, well, what's the harm in referencing it? Well, that brings us to the second reason why people again kind of get freaked out about it. It's because there's a serpent involved. So there's really two reasons why people find the passage confusing or troubling. And that is it involves a serpent and the noun Nakash is used, which is the term used for the serpent enemy, the enemy of God in Genesis 3. So this noun is used in Numbers 21 verses 6, 7 and 9. There's another word also used Saurav in the chapter, Numbers 21, 6 and 8. But we have this reference to the Nakash in this passage. So Moses is going to build a bronze Nakash. And also when Jesus does reference this passage, you know, the Son of Man being lifted up just like the serpent in the wilderness was lifted up. It just feels kind of weird that Jesus would use as an analogy to his impending crucifixion, an episode that involved Nakash. Okay, this term, you know, the serpent. Again, because it's a term that goes back to the Garden of Eden story, Genesis 3, you know, the great enemy, the Nakash that will be later called the devil and Satan. So we look at sort of this agglomeration of ideas.  And it looks really confusing because precisely because all of these ideas are floating around in our head. But that's the point. These ideas are floating around in our head. Okay, the Israelites experiencing this event in real time know nothing about Jesus. They know nothing about the cross. They don't even know, and this is going to sound controversial, I would suggest you they don't even know the story of the Garden of Eden. We assume they do because we do. And we assume that there's this confusion here in the Bible, quote, unquote, in the Bible, because we have the whole Bible and we have all of these things. And we sort of blend them all together. You know, they go in the same file drawer in our heads and we read the Numbers passage or Jesus, you know, statement about the Numbers passage. And we immediately bring the serpent enemy from Genesis three into the discussion. Okay, there is nothing in any of these texts that references Genesis three specifically. And again, I'm going to repeat my own, you know, position here my own thinking to start off with. I don't think I think there's a very good chance that no, no Israelite, none of the Israelites had even heard of the serpent story in the Garden of Eden. Okay, when when this event is happening in real time now that that's going to take some unwrapping because I know that in and of itself sounds a little odd. But I'm suggesting to you and I want you to start thinking about this that it sounds odd because you have an entire Bible. You cannot assume that an Israelite had the entire Bible and frankly you can't even assume that the Israelites living in Moses day had any Bible at all. So this confusion that that that is in our heads about this passage and about the Garden of Eden story and about Jesus referenced to this is a manufactured confusion. Because in our heads, all of those things are circulating when in the text, none of those things get linked to each other.  He has no reference back. He's not talking about Satan. He's not talking about Genesis three. He's talking about numbers 21 and numbers 21 is not talking about Genesis three. And in real time, again, the people living numbers 21, the people who are getting bitten by the serpents and Moses do something before we die. And Moses creates the broad serpent. They look at it and they live. None of those people were thinking about the Garden of Eden either because they didn't have the story. And chances are they'd never even heard of the story. Now let's unpack that a little bit. You basically have, I mean, this gets us into this whole mosaic authorship issue, at least peripherally, at least a little bit. But this topic or passage, again, invariably takes us in, takes us that direction because again, we have the whole Bible. And so we're naturally thinking that everybody else does too, or did. When it comes to the issue of Genesis three, did they know about that? You basically got two options. I mean, I'm going to exclude higher critical schools here, JEDP, you know, kind of stuff, you know, because it's speculative, you know, about sources that existed and how sources were mixed and matched and when they were written, all that kind of stuff. You know, again, excluding that, if you're sort of a person with a high view of Scripture, you basically got two options. One is that Moses wrote Genesis three. Okay, you accept that out of the gate. That's your starting point. Moses wrote Genesis three. Hey, Moses is the guy in the story of Numbers 21. And so again, mentally, you assume, you assume again, without any actual data that Moses, this is going to sound comical, that Moses had written Genesis three and that everybody there had read it. Okay, now, aside from the point of that being logistically impossible, how would Moses write this? Here we have one copy of it now. I wrote the story, Genesis three. And now, if you take the low estimate of the numbers, if you don't take the numbers literally, okay, for the wandering Israelites, if you got a few hundred thousand of them, what are they doing? Passing a stone tablet around? Are they passing, you know, the text written on an animal skin? Are they passing it around? Again, it's absurd to think that even if Moses wrote it right there, right before the event in real time that anybody knew it. Again, you have to make amazing logical leaps to get to that position, that idea. If it's a few million people, well, then the problem becomes even more absurd. I'm hoping you get the picture. So even if you think Moses wrote Genesis three, and this is the standard view, you have problems. But let's think a little bit more about, again, the standard conservative view here. Standard conservative view, again, would say, okay, we got Moses wrote the Torah, which of course includes Genesis. And when did Moses write that? Probably, again, if you read, again, conservative books about this. Moses would have been writing the content of the Torah and Genesis, at least the stuff that wasn't the law and the legal stuff during the wilderness wandering. And he probably wrote the law when they're at Sinai, but now here we are wandering around the desert. So Moses has lots of time. I don't know how he has lots of time while he's walking around for miles, but we'll just say, okay, he has lots of time to write. Maybe he's doing it at night. He has his day job leading the people through the wilderness, and his night job is writing the Torah or whatever. But he has lots of time to write, so he's writing, again, during the wilderness wanderings. So the standard view also, again, if you think about it, actually has to argue that God kind of mentally downloaded the content of Genesis 1 through 11 into Moses' head. In other words, Moses couldn't write Genesis 1 through 11 by experience or by the traditions of his own people, because this is all primeval history. And again, this is the standard conservative view. That part of the doctrine of inspiration would allow them, at least the way they understand it, allow them to say, well, when Moses was writing the Torah, again, a lot of that stuff, from Genesis 12 on, you've got family history, the history of Abraham, Isaac, Jacob, and they're the descendants of Jacob, going down to Egypt there, the 12 tribes and all that stuff. And so you're getting into contemporary material for them. But the Genesis 1 to 11 stuff, the stuff before Abraham, there's no sense that anybody has any record of that. So God has to give it directly. And he gives it directly to Moses, and Moses carefully writes it down. Again, this is the standard view of how we get Genesis 1 through 11 in terms of a total commitment to Mosaic authorship. Again, part of the standard sort of traditional conservative model. So Moses gets this information, didn't know it himself, God has to provide it. Again, Genesis 12 through 50 is a little different because Moses could get this information from his ancestors, or his ancestors' ancestors. Again, the standard conservative view is that the stories of Abraham and Isaac and Jacob were orally transmitted by the family. You know, by the members of the Israelite nation, because this was their family history. They tell it to each other. They pass it down from generation to generation. The stories of how Abraham was called and what happened to him and Isaac and Rebecca and then Jacob and the 12 tribes and Joseph's trip to Egypt. This is all something they knew by oral transmission. And in Moses' day, Moses codifies it. He writes it down. Again, it's very possible. And this is how oral traditions, oral cultures work. Oral transmission is done with a high degree of accuracy. And then eventually it gets written down. For those of you who are over 40, maybe over 50, this takes your mind back maybe to the scene and roots.  And he sits there for days listening to this guy recite the oral family history.   That's real. Okay, when it comes to oral cultures, that is how it's done. And it's done with an amazing amount of accuracy because that's all they have. They don't have TV. They don't have books. It's an oral culture.  There are select people who do this to memorizing the entire history of the clan. And so again, this is something well known anthropologically speaking from all over the world and the Israelites, you know, don't have to be any exception here. So again, the standard conservative view is that this is how Moses, when he sat down to write, got the information about Abraham, Isaac and Jacob. He had someone transmit it to him orally. He writes it down. Genesis 1-11, though, has to sort of drop from heaven because that isn't again part of the family history. That's something that God has to tell Moses. And then after you get to the end of Genesis, where are you at? You're in Moses' own day. Exodus 1. There was a Pharaoh in the land who didn't know Joseph. And then we get into the history of Moses. So Moses can write that stuff and then you get the law. You get the story of the Exodus. Moses is there for all this. And he's there for the giving of the law. He's there for the wilderness wanderings and all this stuff. And so everything else in the Torah, again, in the standard conservative view is easy to attribute to Moses until you get to Deuteronomy 34 when he dies. You know, did Moses write the account of his own death, all that kind of stuff. So this is, again, a very typical way of looking at Mosaic authorship of the Torah. And so when it comes to Genesis 3, those who believe Moses wrote that would say that God gave him that story, gave him that information, and he wrote it at some point during the wilderness wanderings. Well, all of that means, again, all of that leaves you, I should say. All that leaves you with the realization that we don't really have any actual evidence that the Israelites living the events of Numbers 21 would ever have heard the story of Adam and Eve. Again, before they're getting bitten by these fiery serpents again to make some sort of association. Again, an association that we make because, you know, we read Genesis 3 before we hit Numbers 21. And these two things just sort of glom onto each other in our heads. Well, the Israelites, that's not happening because you don't know when Moses wrote it. You can't say there's nothing in the Bible that points to the idea that Moses had already composed Genesis 3 and then this incident in Numbers 21 happened. We have no idea. There's actually nothing to hang this hat on. It's all entirely unknowable. And so the odds are just as good that the Israelites would have never read Genesis 3 and the account didn't even exist for them to read. Even if it did exist, are they passing it around to all a few hundred thousand or a few million people? Again, it's just kind of ridiculous to assume that they knew this story of the Nakash in Genesis 3. Now, of course, once it does get written down, and again, depending on when you think that is, then that's going to be part of how the Israelites think about not only their own history, but the history of everything, the history of the whole world and the human condition and all that, just like we do. They're going to have that material to read and reflect on. Now, the second view other than Moses wrote Genesis 3 is surprise, surprise, Moses didn't write Genesis 3. And I actually think this one makes more sense. This is actually my preference. And that is this view. And I've expressed this view before on the podcast that Genesis 1 through 11 was written later than Moses' lifetime. I personally think Genesis 1 through 11 was written during the exile in Babylon since, A, there are many specific textual, philological, that's linguistic kind of stuff, philological connections, very specific connections to Babylonian or Mesopotamian literature in general in these 11 chapters. And secondarily, B, that was A, this is B. My other reason for thinking that was written during the exile is that there are very few specific Egyptian connections in Genesis 1 through 11, which you would sort of expect if it was composed in the immediate Mosaic era. Again, instead of Genesis 1 through 11 taking shots at the Mesopotamian gods and the Babylonian stories, you would expect it to be taking shots at the gods of Egypt because, hey, we just left Egypt.  But you don't get that. You get a very, very distinct Mesopotamian flavor to Genesis 1 through 11. And so that's where the Israelites are in exile. They are in Babylon and a lot of the material in Genesis 1 through 11 is specifically dissing Babylonian religion, Babylonian deities, all this sort of stuff. It's to blacken their eye, so to speak. And you don't really get really, there's very little that could be sort of tied into Egyptian material in Genesis 1 through 11. So that's why I think it makes more sense to have Genesis 1 through 11 written later than the Mosaic era. Again, by someone else in the believing community that God chose to write that. In my view, I actually chose to append it to material that begins with the family history of Israel, Genesis 12, onward. Which, again, I don't have any trouble assuming that you could have had Mosaic authorship of a lot of that. A Mosaic hand directly involved in that. Who knows? I mean, ultimately, we don't know. But what I'm talking about here is Genesis 1 through 11. I'm not in the JEDP camp, and I'm not in the traditional conservative camp either. Because, frankly, I think both views have points that just don't make much sense. One other comment, just by way of illustration, you say, well, Babylonian flavor to Genesis 1 through 11. What are you talking about, Mike? Okay, Genesis 1, there are specific points of contact to Enuma Elish. You know, the story of Marduk's elevation to supremacy. Marduk was the chief deity during the Babylonian era, 6th century BC. Lo and behold, that's the time of the exile. And when I say specific connections, I mean, there are places in Genesis where the Hebrew of Genesis mimes or mimics the syntax of Enuma Elish. Specifically in Genesis 1, 1 through 3, by the way you have that happen. So there's even grammatical congruence in the way the writer wrote. Where's the position of the verb? Where's the position of the conjunction? Where's the position of the noun? It mimes certain lines in Enuma Elish. And again, to a literate reader, someone who knew both texts, the reason for doing that would have been very evident. And would have been very obvious as well that the writer of Genesis wants you to think of the Babylonian story because he's going to poke it in the eye. He's going to diss it. He's going to turn it on its head and make a different theological point. Well, you need the text of Enuma Elish to do that. So is Moses like carrying one around in the desert? He couldn't in this case because it hadn't been written yet. The one, Enuma Elish, the elevation of Marduk was written in the 6th century. This is centuries after Moses lived and died. So it's a clear point of incongruence. Another example, Genesis 2 and 3. Garden of Eden story. Again, they have the serpent story in the garden. There are some clear similarities between that material and Gilgamesh. Another one called Adupa, a text called Adupa in the South Wind. Genesis 5, again, the list of genealogies scholars have known for a couple centuries. Since the Sumerian king list was discovered, that the list of kings in the Sumerian king list pre and post flood, that there's a relationship between the list of names and the events in Genesis 5. Again, there are just connections there. So again, for that to make any sense, the writer would have to be doing something deliberate with that text, with that Sumerian text. Genesis 6, 1 through 4. We've talked about this before in Unseen Realmen on the podcast. The story of the Apkalu, drawn directly from Mesopotamian material. Genesis 6 through 9, the flood story. You have parallels in the Erodo Genesis, the Epic of Gilgamesh, the Atrahasis Epic. Again, down even to the birds that get let go, and do they come back, and the building of an ark, and the animals, the whole thing. It has differences. Again, there are differences in the accounts, differences in the story and the way they're told, but there's a lot of specific connections.   They just go the other way with it. They don't really think about what's happening in the text, because, frankly, they're not biblical scholars, but anyway, they're usually religion scholars or something like that, or just somebody they stuck in a humanities class to destroy somebody's faith. That's just the way it goes. Genesis 10 through 11, Babylonian map of the world. What's Genesis 10? The table of the nations. Again, what the table of the nations shows is that, again, Israel's not included in that table, but it has the same orientation. Again, the Eastern Mediterranean, well, the whole Mediterranean, but largely the Eastern Mediterranean and then the Middle East. Babylonian map of the world has some congruences there. You have the stories of Nimrod, the closest candidates to identifying Nimrod are, guess what? They come from a Syrian material. That's Mesopotamian material. You have a reference to a ziggurat, the Tower of Babylon. It's Mesopotamian. Genesis 1 through 11 is littered with Mesopotamian elements. I doubt that Moses was hauling a library of Ceneiform tablets around with him in the desert while delivering Israel in the Exodus from Egypt. Now, yeah, Moses maybe could have read Akkadian. Akkadian was the language of the day, kind of like English is. It was the language of correspondence. The best evidence for this is actually evidence that aligns with the late date for the Exodus, which a lot of, again, conservative Bible believers don't like because they want to go with the early date chronologically, but regardless, Akkadian was the language of international correspondence. If Moses is raised in the household of Egypt and he's going to be somebody important, okay, he may have learned Akkadian, at least enough to read a letter or whatever so that he knows what's going on in certain parts of the empire. I get that, but some of these things that I've just mentioned in this list, we're not composed. We're not composed during the New Kingdom period, during that same time period. They were composed later. So again, it just doesn't make sense to argue for mosaic authorship of these things. And again, to me, the biggest argument is that Genesis 1 through 11, the connections that are there are polemic. And again, you would expect if Moses was writing it in an Egyptian context, their deliverance from Egypt, that he'd be dissing the Egyptian gods, but that isn't what happens. That happens like in Exodus 15. It happens in Exodus 12. This night, I will have victory over the gods of Egypt. All that kind of stuff happens with the plagues, but it doesn't happen in Genesis 1 through 11. It's just the point we're making. So what's the point of this whole discussion? What about the story? Again, what I'm saying is that in either view, either view, whether you think Moses wrote Genesis 3 or you think Moses didn't write Genesis 3, either view, it's really, really, really difficult. Naya and do impossible. I would frankly say it is impossible because you have to be omniscient to establish the notion that the Israelites who are experiencing the numbers 21 episode being bitten by the serpents, that they had ever heard of the Genesis 3 story. Okay, my money is on. They never heard it at all. Which again, in part, explains why there are no specific connections between this story and Genesis 3 other than the term Nakash. Well, Nakash just means, you know, serpent when it's used as a noun and very clearly it is here. We don't have a talking serpent. We don't have any indication in numbers 21 that we're dealing with a divine being. People are getting bitten by serpents, by snakes out in the desert. That's where lots of snakes live. And the thing that Moses is asked to fashion is very clearly a serpent on a pole. Okay, not a divine being, it's just a serpent. It's all it is. So in our head, reading numbers 21 makes us think of Genesis 3 and then we go, oh, this is kind of a spooky passage. Does it have anything to do with Genesis? And Israelites never even ask in that question. It's not even on the radar. So that's the first thing we need to sort of get straight in our heads. And I think that the point of the story, if you're able to do that, the actual story itself is pretty self-explanatory. I hate to be a downer here, but it kind of means exactly what it says. There are a few things maybe lurking in the background we'll talk about over the next few minutes, but there's no mystical, mysterious, cryptic connection. Between numbers 21 and Genesis 3. And therefore, since that's the case, when Jesus uses numbers 21 for an analogy about the crucifixion, again, he's not taking some mystical swipe at the devil or something weird going on. Again, that's just a product of our imagination. It is not a product of the text. Now let's go to numbers 21, spend the rest of our time actually in the actual story. So again, I think we could start around, let's just go to verse four. From Mount Hor they set out by the way of the Red Sea to go around the land of Edom, and the people become impatient on the way they start griping. And then I think a key line here, the people spoke against God and against Moses. Any time you speak against God, it's probably going to draw a reaction. And in this case it does. Sometimes it's compassionate, sometimes it's judgment. Here we got a case of judgment. They ask, why have you brought us up out of Egypt to die in this wilderness? Now commentators have noticed that the way this is worded in Hebrew, and you can sort of get it in English as well. It's very close to the Dathan and Abiram language, the language of complaining back in number 16. And again, that would sort of connect the two episodes being another one of these episodes where the people are not only grumpy and impatient, but they're there of the mind that, oh, we had it better back in Egypt, which of course by implication is you're not here in slavery and then the gods of Egypt are your superiors, that kind of thing. And that's offensive. So that's going to draw a reaction from God. It's not only a rejection of Him. It's not only a rejection of the events that are preceded like the crossing of the Red Sea. It's also very clearly a rejection of the provision of the manna where the people say, we hate this word. We love this worthless food. The stuff that God has been giving them. They don't like it. They grumble about that. So in response to, again, hearts that are hardening to borrow, again, another Exodus metaphor here. In response to the Israelite grumbling and unbelief, Yahweh sent Ha Nakashim Ha Serafim. Okay, you have both terms, both plural, used side by side. So we have typical translation is fiery serpents. Okay, Ha Nakashim Ha Serafim. So fiery serpents, you know, that's an okay translation. Again, I don't think there's anything really terribly weird again going on. I think the fiery part, again, would refer to the burning metaphorically of the venom because they're getting bitten by snakes.  Oh, well now here we have like divine beings that are serpent people or dragons or fang demons or snog. They're just snakes. Okay, and this language, again, is used elsewhere of just snakes that when they bite you, it burns because they're venomous. It's really all it means. Now, in regard to this though, there are some people who would try to make it more than that, not only on the basis of the Serafim, but just the term, but they would look back at Isaiah 6 and say, well, the Serafim had wings and they're flying around. And, you know, now back in Moses' days, snakes must have been able to fly if they're just snakes. And then they'll point to Isaiah, there's two passages in Isaiah that marry these terms, the Nakashim and the Serafim to another term, met-of-faith, which means flying. Okay, so Isaiah 14-29, just to quote it for you in the ESV, rejoice not, Ophelistia, all of you, and the rod that struck you is broken, for the serpent's root shall come, from the serpent's root shall come forth an adder, and its fruit will be a flying fiery serpent. And then Isaiah 30 verse 6 has similar language, an oracle on the beasts of the Negev through a land of trouble and anguish, when there come the lioness and the lion, the adder and the flying fiery serpent, blah, blah, blah, blah. Again, all the other animals in that list are normal, by the way. But the argument goes that we have a dragon here, we got something weird going on. The terminology, and I've referenced this article before, and if you have unseen realm and you're reading in the little section where I talk about the Serafim, you're going to get this article. But there's a really nice article in, I think it was Biblical, the journal Biblical, a guy named Proven Kahl on the Serafim, the fiery serpents. And he goes into the iconography and whatnot. The flying description is really pointed at, it's not a dragon. It's not like a fang, demonic, bat-winged extraterrestrial or something like that. So let's try to get the cartoons out of our head. What it's aimed at is, if you've seen like an Egyptian Euryas, the cobra, the winged cobra, we modern people like to call it. We know cobras don't fly, we know they don't have wings. But what they do have is they have these flaps of skin on their side that expand. That's what it's talking about. They look like wings. So these descriptions of flying fiery serpents are those guys. They're serpents, again, with these sort of wing flaps on the sides of their head that extend down their body a little way. And it creates the impression, again, the visual impression that they have wings. That's all it's talking about. And again, these are common. These kinds of serpents are common in the region. They're common in Egypt. They're common in the Negev. Again, because that's where they're walking around here in numbers 21. And they're poisonous. So God, again, sends a bunch of these, these kind of serpents, cobras, whatever, if you want to use that term, but venomous snakes against the people to punish them. So that's the story. Again, it's pretty straightforward, pretty self-explanatory. Now, in response to their repentance, the people say in verse seven, people come to Moses and say, hey, we've sinned like no kidding, for we have spoken against the Lord and against you, pray to the Lord that he take away the serpents from us. And so in response to their repentance and Moses' intercession, God tells Moses to make a Saraf, make a Saraf and put it on a pole or a banner. That's the term there. That's one of them that's used in here. But then when Moses actually makes it, it's called the Nakash Nakoshet, the bronze serpent. And these two verses here, verses eight and nine, show us that Saraf and Nakash are being used interchangeably, again, for a normal snake. But of course, when Moses fashions it, he's going to fashion it out of bronze and mount it on a pole. Now, here's where you actually start to get into, I think, some worthwhile questions as far as, well, what the story is kind of straightforward, but what's the meaning of it? Like, what's going on? What are they thinking? Why is God telling them to do this? And here's where, again, in the academic discussion, you get, again, some variants of opinion. A lot of overlapping, but there is some variance here. Serpents, most scholars will point out, were associated throughout the ancient Near East with healing. And you ask, well, why? What is there about a serpent that an ancient person would look at it and associate it with healing? Or, I'm going to give you some hints here, or rejuvenation, or even the spontaneous appearance of life, the origin of life, that kind of thing. Why would a person look at a serpent? Why would an ancient person, why would Egyptians, why would Mesopotamians, why would Hittites, why would Canaanites look at serpents and associate them in some way with healing, with fertility, the bringing forth of life and rejuvenation? Well, it's because they shed their skin. It's like they become new. And to the ancient mind, to the ancient eye, it was like a rebirth. It was something, a new thing coming out of the old thing, and the new thing is better than the old thing. It's rejuvenation, it's the origin of life. And again, this whole healing idea. So this is why ancient people tended to look at serpents this way. And this belief, this belief is probably the wrong word, but this notion, this conception of what was happening to a snake when it shed its skin is reflected in ancient Near Eastern iconography in many places. There are many examples. I'm going to give you a couple of quotations here. The first one is from DDD, the way of deities and demons in the Bible. And the entry on Nakhush, it's either Nakhush or Nakhushtan for this entry says, quote, the use of snake images to affect the cure of venomous snake bites is consistent with the ritual symbolism of snakes in the ancient Near East. In Egypt, snake amulets would be worn by the living or the dead to ward off venomous snakes. The Urea serpent, by the way, the dead referenced there in some of the books of the dead, but the big enemy to getting into the positive afterlife was Apophis, the serpent. You had to wear the serpent thing to ward off the other serpent, but that's not rabbit trail too much on that. The Urea serpent protected gods and kings from danger in one of the symbols of the Pharaoh. Because of his snake nature, the king was immune to snake venom and could cure others. Again, because he had aligned himself with the snake god, the protector that the king was immune to bad snakes and could heal and all this kind of stuff. This is part of Egyptian religion and part of Egyptian mythology. Protective snake figurines are also found in Mesopotamia, including reliefs and amulets of two snakes entwined. Again, you've all seen this symbol with the two snakes going up the pole wrapping themselves sort of together. The symbol was later inherited in Greek culture as the healing symbol of Asclepius. We refer to it as the Caduceus and you'll still see it in medical insignia today. It's a very old symbol. Another quote, this is from Karen Joins book, Serpent Symbolism in the Old Testament. This isn't a direct quote I'm just going to summarize here. She's citing a guy named William Ward who was an expert in Egyptian scarabs. But Joins' citing Ward notes that the Caduceus has been found on Babylonian cylinder seals as well. Not just scarabs, but Babylonian cylinder seals from as early as the 4th millennium BC, so into the 3000s BC. In that case it was probably a fertility symbol though and not a healing emblem. Serpents were widely associated with life. That is the origin or the spring to life, the rebirth of life again because of the things we've talked about. So they were often fertility symbols and that's typically what you see in the Mesopotamian context but you also get healing there too. So, again with that as sort of a backdrop what's going on here with Moses and the Israelites in their context. Some have taken this propensity or this ancient this common conception that serpents again were associated with healing and they look at what's going on in the Numbers episode and to them it really, to many scholars it's a fairly clear example of something called sympathetic magic. Now if you're unfamiliar with that term sympathetic magic is where the cure for a problem is achieved by fashioning a physical object that relates to the problem or looks like the problem or in some way is associated with the problem in order to combat the problem. You could also produce an object in sympathetic magic that would produce a certain result again after some ritual. Now I think the latter again this doing something to get a desired physical effect I think sympathetic magic in that sense is almost definitely what's behind the Jacob and Laban story if you remember Genesis 30 I believe it is where they're laying out rods you know these little for lack of a better term these pieces of plants these stems these rods or whatever before the sheep the flocks to produce the kind of offspring that would belong to Jacob the spot of the speckled and all that kind of stuff. Now God he does this but later Jacob says that he gets the idea from God to do this to outwit Laban. To me that's a very clear example of sympathetic magic and what's going on there is God tells him to do this and Jacob believes God. So he this kind of thing would have been familiar culturally again because you have other people doing this kind of stuff and so God says well here's what you do here's what you do to outwit Laban you make this stuff you put it in front of the flocks they'll do their breeding thing and lo and behold this is what you're going to get. So Jacob believes that God will do this and so he responds to this idea and he does what he's told to do and God produces the results. Now is that what's going on in Numbers 21? Well you know if you read it that way kind of you know God says hey make this the serpent put on a pole people look at it after their bit and they'll be okay. So the notion of sympathetic magic in and of itself if you believe the source of the power is the God of Israel is not a theologically offensive idea to an Israelite not to us it's really foreign but again we don't live in this culture you know we're not dealing with this kind of mode of communication you know we don't have God telling us to do these sorts of things again this is God telling someone to do something that would have sounded familiar would not have been completely bizarre in their context and Jacob or here Moses God told me to do this and I believe that God's going to do something with it so let's do that because God is powerful God is able to do whatever he's going to do through this means and I'm going to listen I'm going to do it I'm going to make that thing I'm going to Jacob's incident I'm going to lay this stuff down in front of the sheep and again let him let him breathe and I expect that God will produce the result that I'm going to like and he does well again it's kind of the same thing with Moses so I could see the sympathetic magic idea here in their context Milgram has an interesting quote here in his numbers commentary and Milgram is a Jewish scholar I don't know if he's still alive or not but he has a very well known commentary on numbers in the Jewish Publications Society Torah series he writes the homeopathic use of snakes is a distinctive feature of ancient Egypt so again that would have been familiar to Moses a serpent shaped amulet again was worn by the living to repel serpents and also by the dead often mummies to ward off attacks by serpents and other reptiles in the netherworld again I made the mention of a pofus earlier thus at the time of Moses Milgram writes the belief prevailed in Egypt that images of serpents would repel serpents as well as heal wounds caused by them you're using you're using the like thing to combat the other thing and the thing you know if you know when your God tells you to do this against the other thing you're fashioning the same object you know your God you believe is going to have the power you know through that object to combat this evil thing that is after you that's harming you conflicting you again so the numbers 21 episode reads very similar to that very very much like that Milgram continues it is likely no accident that a copper image of a snake was found at Timna the copper mining region near a lot on the Red Sea dating from between 1200 and 900 BC so sort of a contemporary example obviously not the one associated with the story Baruch Levin comments on this in his numbers commentary and I think it's important to hear Levin as well the incident of the bronze serpent is an excellent example of the interaction of prayer with with magical praxis magical sort of tactics or or acts ritual acts and in no way assails the power of the God of Israel on the contrary it reaffirmed Yahweh's power the many attempts to explain away the account of this incident on the grounds that if taken at face value it would conflict with biblical monotheism reflect misunderstanding of ancient Near Eastern magical phenomenology as known to us from comparative sources and again that's that's Levin's more flowery way of saying what I said a few minutes ago when Yahweh tells you to do this this is not going to be a really you're not going to look at Yahweh and go like hey is there wax in my ears can you repeat that again because that's just kind of weird no they're going to know Moses is going to be familiar with this idea Jacob is going to be familiar with the idea again this quote sympathetic magic is that's a term modern anthropologists use but your God is telling you to fashion an object that your God is going to use to heal your wound or to fix your problem or to deal with the evil thing that is troubling you and so you have to choose to either believe what your God is telling you to believe that your God is powerful or not Jacob believed and did it Moses believed and did it and Yahweh used their obedience again they're following the procedures to produce the results he said he would produce so for an Israelite this isn't strange this is again something culturally normative culturally familiar to us it looks bizarre and when you get anthropologists running around saying oh this is sympathetic magic because we're moderns and again this isn't our world we get a lot of people running around and they'll seize that point and say you can't have monotheism with this you can't have a belief in Yahweh no it's exactly the opposite Yahweh is asserting his power over the situation and the spiritual lesson frankly in Numbers 21 is the God who caused you judgment the God who caused you pain and harm and death is the same God who can take it away he has power over death and power over life life and death are in his hands so there is by definition then if you can fix that in your mind you'll get the ancillary point here by definition you can't appeal to any other power God sent the serpents to punish you the only thing that will take them away is God the only solution to the problem is Yahweh of Israel there is no higher authority there is no alternate source of power that can undo what Yahweh did only Yahweh can undo what Yahweh does and so you are dependent on his goodness to relieve the problem and this is what he's asking you to do end of story so the theological point is very consistent with the elevation of Yahweh what scholars would call biblical monotheism it's not contrary to it in any regard but again you got a lot of fruit loops running around on the internet that take a story like this and again the terms that anthropologists use and they rip it out of context to argue whatever flaky point it is that they want to argue from the passage and it's just not legitimate it's not good scholarship I think that's probably the most succinct way to put it now when Jesus references this I think the associations are quite plain if you don't have the Genesis 3 serpent floating around in your head there's no problem and you shouldn't have the Genesis 3 serpent floating around in your head because again there's no indication the Israelites had ever even heard the story and there's no links in Numbers 21 back to Genesis 3 there's no sense of divine evil beings here they're just snakes that's what they are and God again provides the solution but when Jesus says hey just like Moses lifted up the serpent and the wilderness that anyone who looked upon it was cured and that was the power of God that was undoing the problem of death because they were going to die from the bites if they weren't treated so God commands Moses to make this serpent God says I will undo this thing that no one else can undo no one no deity, no person can deal with I will deal with it if you build the bronze serpent lift it up and tell the people look at it when you're bit you will be healed and Jesus says that's just like what God's going to do here you know we have this problem that the cross rectifies and no other thing but the cross can rectify it this problem of death this problem of human mortality so the son of man must be lifted up again I think a fairly it's not a totally blank reference to the cross but again as you're reading the Gospels you know what he's talking about here his own self sacrifice on the cross and he's saying look this is the solution look upon it and believe if you don't turn to it in faith and believe you're going to die you will inherit death so the analogy is a pretty powerful one but it's confusing to a lot of people in our day because we have Genesis 3 floating around in our heads wondering what in the world's going on well nothing's going on don't import things don't throw things into the blender that the Israelites didn't have in the blender and the writer didn't have in the blender you don't just get to throw other passages in the blender and say oh that looks messy now well yeah it does because you just messed it up so again we need to be thinking more about the the immediate and the larger context of what the writer and what the Israelites had in mind the other thing before we wrap up here the bronze serpent is mentioned in 2 Kings 18 it had survived many years and this is the account where specifically it's 2 Kings 18 1 through 6 and it's part of the Hezekiah story so I'll read it here in the third year of Hoshia son of Elah king of Israel Hezekiah the son of Ahaz king of Judah began to reign 25 years old when he began to reign and he reigned 29 years in Jerusalem his mother's name was Avi the daughter of Zechariah and he did what was right in the eyes of the Lord according to all that David his father had done he removed the high places and broke the pillars and cut down the Asherah and he broke in pieces the bronze serpent that Moses had made for here's why for until those days the people of Israel had made to it it was called Nahush Tan he trusted he Hezekiah trusted in the Lord the God of Israel so there was none like him among all the kings of Judah after him nor among those who were before him for he held fast to the Lord so on and so forth Hezekiah again as part of his campaign against idolatry destroys the bronze serpent of Moses now that account raises a number of questions Nahush Tan sounds like both the Hebrew terms for bronze and serpent so again they gave it a name again using it for idolatrous purposes so there are a number of questions you know what does until those days mean does that mean that the serpent was worshiped from the time of Moses onward? probably not you can't see Moses putting up with that obviously did they worship it from the time of the construction of the temple when they actually got a temple in Jerusalem did they bring this thing in and start to worship it well who knows from some other period before Hezekiah probably more likely because again the Old Testament tells us the story of Israel's idolatry but I think maybe a more interesting question is what did the serpent represent in the Israelite cult the Israelite ritual system and when was it made part of that system again we don't the short answer is nobody knows nobody knows the answer to any of these questions and it's actually very complicated because it takes you into pre do you realize that Jerusalem had to be conquered David conquered Jerusalem and it became his capital city before the conquest of David before he took the city it was called Shalom it's associated with Melchizedek look at the name Melchizedek it's associated with Zadok in the minds of some scholars remember during David's time there were essentially two high priests Zadok and I'm trying to remember the other one drawing a blank here a Biathar so people have wondered well what's going on with that like why do you have two guys instead of one you can't really tell if either of them are Levitical and so there's a really long convoluted and here's the keyword speculative background to what's going on in Jerusalem worship before David becomes king and again if it's pre-Devitic it's just going to be sort of traditional Canaanite and so you have to ask yourself the question after David was there and David does some good things and some bad things he gets the idea to build a temple it's eventually built by Solomon and the ark is moved in there and it has a kaya so what's up with Nakushetan was that in there with the ark did they put it inside the ark is it some object that maybe one of the priests liked because maybe it was associated with religion before David because hey Israelites were doing something before David and they were doing lots of crazy things before David look at the period of the judges people doing what's right in their own eyes there's a lot of apostasy going on intermarrying an interreligious mixture of Israelite thinking and Canaanite thinking maybe somebody saw this object one day it got wherever it was kept we're not even told where it was kept in Moses day but somebody got a hold of it maybe made it a god out of it made it the focus of worship we have no idea what its history was what its history was in relationship to the ark what its history was in relationship to the high priesthood pre and post Jerusalem we don't know any of it and if you read the material you're going to get all sorts of speculation again about what might be the history of this thing all we know for sure is what 2 Kings tells us Hezekiah destroyed it because it had become an object of idolatry we don't know when it did we don't know how that was marketed to the people if it even really needed to be marketed in the days of the good kings whether it was used or not used because to many to many this would have been a symbol of Yahweh that might sound shocking because hey isn't there a command about making no graven image well yeah there is but God told Moses to make this this broad serpent and Moses did and God healed the people so when this happens that's going to have an effect on people it's going to become an ordinary object and so in the minds of even a good Yahweh worshiper this was a I'll use my terminology here carefully this would have been a special thing this would have been a special object because this was the thing that God told Moses to build and it healed people it's important if you're a true worshiper of Yahweh you worship only Yahweh so here's a question to do anything that felt like worship when this snake was involved or would you think well that's just a symbol of Yahweh we know it isn't Yahweh because it was never fashioned God didn't say hey make this brazen serpent because it looks like me this is an image of me he doesn't say any of that so it would have been associated with Yahweh and so maybe even a godly Yahweh worshiper would think well there's nothing wrong with having that as part of some festival or ritual or whatever because it's a symbol of the Lord who knows it's all speculation you have to psychologize the Israelites to come up with a quote unquote answer which really isn't an answer because it's just a guess it's speculation of what they were thinking faithful Israelites and as opposed to apostate Israelites because they're not going to care they're going to make it a deity and off we go but not every Israelites is going to be thinking the same thing and so what was going through their minds with this thing because people knew it they saw it of course when you get the temple the ark's there is it with the ark or not I mean nobody knows so like I said you can do lots of entertaining reading where scholars will try to tie this into the Melchizedek priesthood because of Zadok Zadok being pre-catch this catch the wording here the pre-dividek pre-national Israel priesthood and some would argue because Melchizedek and Zadok are the same consonants that there's a priestly name thing going on here between these two guys Zadok was a representative of a priesthood catch this earlier than Aaron's that was viewed as in that sense more everlasting or more important than Aaron's again and so the real high priest is the line of Melchizedek and Zadok and so once you start again going down that rabbit trail then you know you get stuff like when the serpents show up and again nothing textually ties all these things together let's make that clear nothing textually makes the connections but this is the kind of thing you'll read now I do think again this is getting real far off the rabbit trail so I gotta raid myself in here but I do think that this whole idea of a high priesthood after the order of Melchizedek is obviously legit at Psalm 110 and the way you get that as a superior priesthood over the line of Aaron is to assume is to assume the priesthood of Aaron was a concession to Moses way back in Exodus 4 that he needed help or you could read the here's the nice word it's not an assumption you could read the Mosaic account and see the compassion of God in giving Moses a helper and his brother becomes the high priest but what God really intended was as Abraham meet up with Melchizedek was that someday Abraham's descendants would live in this city and have this priesthood the priest of the most high God and that this was God's design all along for the priesthood and that is why the Melchizedek priesthood is superior and Aaron's priesthood is secondary because God again he gives it to he gives it to Israel because he gave it to Moses Moses needed a helper so you can read the account that way you can sort of make it a bit of speculation I mean again we don't ultimately know but we do know that there was this thing called the high priesthood of Melchizedek we do know that and there was Zadok and there was a Biathar and a whole levitical thing the high priesthood thing is really kind of a hornet's nest when it comes to Old Testament theology because there are lots of ambiguities built into it but if you do any reading I'm telling you all that to sort of condition you if you do any reading on Nakhushtan and again what's going on with Hezekiah and why he destroyed it and how in the world did it become this thing of idolatry you will invariably run into this whole discussion about Zadok and Melchizedek and the pre-Israelite it's called the Jebusite priesthood because that was one of Jerusalem's old names it was a Jebusite land possession there but anyway that's getting quite a bit off the beaten path I'm going to add one more thought there are some who would also say that the religious role of the serpent might be due and again I'm going to tell you upfront I think this one is far fetched but it might entertain somebody here there are some who would say that the religious use of the bronze serpent either during or earlier than Hezekiah's time had something to do with the fact that since serpents were associated with life that we might have the serpent as being a symbol or an artifact of something that modern scholars call the Omphalos myth and the Omphalos myth I'll spell it O-M-P-H-A-L-O-S it's a term that means the naval of the world the center of the earth the central point from which terrestrial life springs and originates now think with me here's how people would defend this idea they would say well Eden look back at the Garden of Eden and you're thinking well Mike I thought you said numbers 21 the bronze serpent has nothing to do with the Garden of Eden yes I did and I do think that so that's why I think this is far fetched but follow me if you will this is how it's defended that's where life's origin was and there was a tree of life in the Garden of Eden and in Mesopotamia the tree of life was associated with the serpent because you got this intertwined serpent neck stuff as a symbol of life Gilgamesh is searching for eternal life and he finds a sacred plant which we identify with the tree of life he loses that when he loses immortality when the plant is stolen by a serpent in the Gilgamesh story and so Jerusalem is the new Eden right you know Jerusalem is the new Eden and so as Eden was the center the wellspring of all life there are people who would have believed that Jerusalem was the wellspring of all life and the serpent object probably helped remind people or teach people that Jerusalem was the new Eden if I had a cricket sound I'm gonna play it right here yeah you'll run into that too again the severe problem with this is how it not only links the discussion back to Genesis 3 but it ignores the evil aspect of the serpent in Genesis 3 which is really convenient and frankly really necessary for that discussion now I will say this the Amphelos idea that Jerusalem is the center of the world that is biblical that is biblical thinking but it has nothing to do with Numbers 21 it has nothing to do with Nechushan it has nothing to do even with Genesis 3 where you see it there's a couple passages there's 2 in Ezekiel I'll read them to you Ezekiel 5.5 says thus says the Lord God this is Jerusalem I have set her in the center of the nations all around her and then in Ezekiel 38.10-12 we have another reference here if you're taking notes Ezekiel 38.10-12 say this thus says the Lord God on that day thoughts will come into your mind and you will devise an evil scheme again this is the passage about Jerusalem getting invaded by Gog and Magog and all that stuff Gog of Magog on that day you will devise an evil scheme against the land of unwalled villages so Ezekiel is kind of mouthing what Gog is thinking the great enemy I'm going to go up against the land of unwalled villages I will fall upon the quiet people who dwell securely all of them dwelling without walls and having no bars and gates verse 12 to seize, spoil and carry off plunder to turn your hand against the waste places that are now inhabited and the people who were gathered from the nations that are real interesting line the people who were gathered from the nations who have acquired livestock and goods who dwell at the center of the earth okay so it's this idea that Jerusalem was sort of the center of all things the center of the earth so that idea again is part of biblical thinking it's because this is Yahweh's place Yahweh is the source of life Yahweh is the source from which all life brings, everything to work the metaphor, everything revolves around Him and where He is and that was Zion, that was Jerusalem so this idea is part of biblical thinking and part of biblical theology but it has nothing to do with the Hush town, the Brazen serpent and all this sort of stuff so to wind up, I think numbers 21 makes sense just as it is, makes sense at face value, it wasn't connected to Genesis 3 at all that you know you have a Mosaic Yahweh symbol that winds up getting perverted into idolatry oh well okay the Israelites turned the whole system into an idolatrous system you know why would we be shocked that an object that in Moses day would have been associated with the power of Yahweh why would we be shocked that gets used later on for idolatry and Hezekiah has to destroy it I don't find it shocking at all given what we read in the Old Testament about the Israelites basically they're prone to do almost anything with almost anything in terms of idolatry so again I think these passages are pretty easily understandable in their own terms, the other theorized elements are interesting but they're ultimately only speculation Mike what's your thoughts on Genesis 6 or the men of renown with the Greek gods the god of healing, what is his name? Asclepius yeah there you go I don't think that there's it's going to be serpentine stuff and I don't see any connection there with Genesis 6.4 He's the god of healing who symbolizes a brass serpent on a pole and you get Hermes with the two serpents intertwined on a staff are there any connections there not in terms of the language I mean every I think I've mentioned this before on an episode but if you're interested in how Greek material was influenced by and repurposes ancient near eastern material like the Mesopotamian stuff here the best book to read is called the East Face of the Helicon it's by M.L. West it's a bit hard to find I think it's out of print unless they brought it back into print now and it's also a little pricey but there's nothing else like it so you do have connections between Greek stories, Greek myths, Greek characters Greek deities and quasi deities and ancient near eastern material and since there's a connection between ancient near eastern material and biblical material because we have more of a chronological overlap there and a geographical overlap there you're going to you're going to see reflections in all three in other words you're going to see commonalities between all three but what you can't you can't really say that the biblical stuff is based on the Greek again because there's a chronological problem with that you're going to have to see the Greek sort of responding to and interacting with and repurposing the same kind of stuff that the biblical writers are bouncing off of but the biblical writers are doing it for altogether different reasons they're doing it for polemic reasons rather instead of just hey I like this story and I'm going to use this to tell a story over here as opposed to making a theological point so there is some difference in strategy as to why writers would do what they do but again the stories do get you get these common reflections of each of them and the Titan story in the Greek there's actually two versions in ancient Greek literature of the Titan story that are not free of contradiction and a lot of people who talk about the Titans don't realize that they're actually two different stories but one of them again is very close to the elements of Genesis 6 and the other one isn't so close but you have retelling in those terms as well about what happened before the flood, what happened after the flood because there is this flood thing going on in most of the ancient Near Eastern energy and world and so you have common touch points with those with those events well we need to switch gears here and as everybody probably noticed the new website's up I just want to remind everybody it's still a work in progress but it's still cool even if it's a work in progress it's a big improvement I like it it's awesome I think Joe did an awesome job on the website and the new images and he's doing the majority of the heavy lifting and then I will probably be bringing the podcast into drmsh.com at some point and doing some tweaks here and there so just want to give Joe and his team a big thanks for all the work that they've done a lot of work we did an episode on how the development of the New Testament came about so next week we're going to tackle the Old Testament we'll talk about where we got the Old Testament there are there is conspiracy talk associated with that we'll get into that a little bit it's not as familiar as the King James only stuff but we'll try to do something a little weird you know with that one but yeah it's only fair that 3 quarters of your Bible the Old Testament gets equal time okay again just want to thank Joe and his team for all the work they've done and thank everybody for the patience for that and for listening to the Naked Bible Podcast God bless thanks for listening to the Naked Bible Podcast to support this podcast visit www.nakedbibleblog.com to learn more about Dr. Heizer's other websites and blogs visit www.brmsh.com


Now we can take a look at pendulum simple harmonic motion. And we're going to take the case of a simple pendulum. Now over here I've got a simple pendulum animation going. And there's a couple of properties that need to be in place for us to be a simple pendulum. One is it must be a thin string, meaning it's not a lot of mass in that string, not a lot of inertia. But the length of the string matters. And I can either use the symbol of little l or big l to represent the length of that string. You'll see both of those in different textbooks. There's got to be a mass out on the end of that string. And I'm going to give it the symbol of m. And the last thing is it has to be a small amplitude. What does that mean? Well imagine I take my pendulum here and I draw an imaginary line straight down. And so I'm watching it oscillate back and forth to one side and then the other. The amplitude is sort of the angular measurement of how far angle wise it goes from one side to the other. And that needs to be a small angle. Now we know to have simple harmonic motion we have to have a restoring force. So if I look at the forces on the pendulum which are tangent to the path and I look at the angular acceleration, I end up finding that the angular acceleration is approximately equal to minus g over l theta. I'm not showing you in this particular video how we came up with that equation. Now this approximation here is a pretty good approximation for small angles. That's why our simple pendulum had to have a small amplitude. And by small angles we really mean something which is less than about 0.2 radians which is about 10 degrees just to give you a feel for that. Now looking at this equation I've got my acceleration and my position. In this case it's angular acceleration and angular position. I've got gravity as my g, my length which is my l and those things are constants for a particular problem. And I've got a negative sign in there and we have to have that negative sign for it to be a restoring force. So this is of the form of the restoring force we need for simple harmonic motion. Now since we know it's simple harmonic motion it's going to oscillate with an equation similar to our general one. Although we have a few differences in here. My position is not x anymore it's the angular position theta. I've still got it being a function of the variable time. Now instead of having a capital A I'm using my theta max to represent my angular amplitude. But I still have an angular frequency and a phase just like my general equation. Now in terms of my pendulum's omega value or its angular frequency because this was my equation for the acceleration remember that the negative sign out front tells me it's a restoring one. I needed to have some problem specific constants and in this case it's g over l. So my omega squared for this particular problem is g over l. Or I could write that as omega is the square root of g over l. Now remember that omega is the angular frequency. My g is gravity and l is the length. So for any particular pendulum once you decide whether it's on earth or the moon or wherever it is you know your gravity value. Once you set the length of that pendulum that means the angular frequency is set by those objects. So now we can talk about the pendulum period. Remember that the period is related to the angular frequency by 2 pi over omega. And since my omega was the square root of g over l that means I could represent my period as 2 pi the square root of l over g. Because my omega was on the bottom it flips my fraction. That means a longer length is going to result in a longer period. And if I could somehow alter the gravity that would also alter the period of the pendulum. So that's a pendulum operating in simple harmonic motion. Just a brief introduction to the simple one.


Now, speaking of databases, we can finally talk about model modules. Earlier when we laid out the whole lifecycle of how Web2Py handles a single request, we skipped over one step, and that is that before the controller module is executed, the model modules of the application are executed. So what purpose are model modules supposed to serve? Well, mainly their purpose is to be the place where we put the code that defines the database schema and opens any database connections we need. That's why they're called the models, because in MVC architecture the model is the area concerning everything to do with the data of the application, the data persistence and storage. In Web2Py, though, these models tend to be also the place where we set any configuration variables our application might use, and the reason we glob that stuff together with the database stuff is, well, it's just convenient. That's because any name which we define in these model modules, any name you create in the namespace, if you define a function or if you assign to a variable, Web2Py takes those names and automatically imports them into your controller module and also into the views that get executed. So, for example, when we open a database connection, we typically assign the object representing that connection to a variable, which we usually call DB. And then in our controller module, we can simply refer to DB, and it's just there implicitly, because Web2Py makes sure that anything that you define in your model module is going to get carried over. And in cases where more than one model module gets executed, then all the stuff defined in the earlier modules will be available in all the later modules. So if I have model module A and model module B and A runs first, well, then anything we defined in A will be accessible in B, and we don't have to explicitly import anything. Web2Py makes it happen automatically by the means that we discussed earlier where it will execute models using the exec statement and the exec file function rather than use the usual import statement. So to sum up this automatic importing business that Web2Py does, first, the model modules run, and everything you define in one of those modules is visible in every module that runs subsequently thereafter. And then after the model modules, the controller and then the view modules execute. And while everything from the models is visible in both the controller and the view, the definitions in the controller module are not carried over automatically into the view. The only way things pass from the controller to the view is when you put them in the dictionary, which you return from the action function. Now the question that remains is, for a particular request, which model modules are going to run? Well, first off, all the model modules are included in the model's subdirectory of your application directory. And all the modules directly in that directory are always run for every request. However, any modules placed in a subdirectory of the model's directory only the directory with the name matching that of the controller and the action of the request, only the modules of that one subdirectory of the model's directory get executed. So for example, the modules in the subdirectory models slash foo slash bar, those only get executed in a request where the controller is foo and the action is bar. Similarly, any modules found in just models slash foo, those get executed when the controller is named foo no matter what the action is. Now finally, as for the order of execution of these model modules, well, within each directory, they are run simply in alphabetical order and the order of the directories is that first the model's directory itself is always run first, then those modules, if any, in a subdirectory matching the controller name, and then if that directory has a subdirectory which matches the action name, the modules in that directory will run. So for a single request, at most the modules of three different directories will run and execution always starts with the model's directory itself and works downwards through the subdirectories. Now I would say in a large majority of applications, you're not going to want to have any controller or action specific models. You'll just have everything in the model's directory itself. And within that directory, you may not have much cause to have more than just one model module. You very likely may not have any reason to split that one file up into many, as long as it doesn't get too big. In my own Web2Py applications, I tend to start with just two model modules, the first for defining my schema and then the second for defining what's often called business logic. Basically, it's an API of functions I create to then use in my controller and view modules so that my controller and my view modules don't have to know anything about the internals of the structure of my database schema. How exactly a so-called business logic layer and the reasoning behind it, that's something we'll discuss probably in a supplementary unit in which we actually create a real Web2Py project. The component of Web2Py used to access databases, it calls the DAO as in database abstraction layer. And as the name implies, it's a library that abstracts over database access such that using this API, we don't actually talk to the database in SQL. The abstraction layer provides objects and methods which, when we use, usually gets translated ultimately into SQL. Now, I said usually because some databases which the DAO provides access to aren't actually relational databases using SQL. The DAO supports the database provided by the Google App Engine, which isn't a relational database. So when using the DAO to abstract over the Google App Engine, there's no SQL involved. The methods we invoke with the DAO will get translated into whatever the Google App Engine uses, I'm not familiar. It's something other than SQL, is the point. The only caveat to this is that because the Google App Engine is not a SQL database, it's not a relational database. There are some operations with the DAO which don't apply to the Google App Engine. So if you're using that as your back-end, certain methods just don't do what they normally do with other back-ends. In other words, the abstraction layer isn't perfect because all these back-ends, they can't be abstracted over in exactly the same way. For most of them we can, more or less, because they're all relational databases using SQL, but even there, there's some differences in what features they support. So for the most part, though, the DAO operates transparently no matter what your back-end is, that is, for whatever your back-end, it gives you the same apparent behavior. Now, at the moment, the DAO has support for a good number of different data back-ends, including SQLite, Postgres, MySQL, the Google App Engine, Microsoft SQL, Oracle, and a number of other options, though these are probably the most commonly used. Now, only one of these will really work out of the box when you install Web2Py without any further setup, and that's SQLite, because SQLite is natively supported in Python itself. In the case of MySQL, I believe support comes built in. If you're running on Linux, if you're running on Windows, though, I think you need a driver, you need a database driver. Postgres, you need to install a certain library to get Postgres working with Python, and it's basically a different case-by-case. So there's a little bit of configuration work to get those working with databases other than SQLite. Now, to actually use the DAO, the first thing you're going to want to do is create a connection. A database connection object is created with the class DAO, found in the module gluon.DAO. And to the constructor, we pass a so-called connection string. Database connection strings are just strings containing all the information the database needs to establish a logon. And for most databases, the connection string is expected in the form of a URI, like this one here for Postgres. And it's specifying first my username, Brian, with the password, my password. And then it specifies the host with the port, localhost, and port 5, 4, 3, 2, which is the default Postgres port. And then after the slash, we specify the name of the database. Because remember, for one instance of Postgres, that's a database management system, which potentially has more than one database. So you create a database within the management system, and that database has a name. So here, this is connecting to the database name thing. And assuming there's a user account, Brian, and this is the valid password, and assuming that account has access to a database name-to-thing, then this is a valid connection string. And Web2Py should successfully create a connection object. And we're assigning the connection object here to the variable named db. And that's a well-established convention in Web2Py is to always name it just db. The only reason you'd need to name your connection object variable something else is if you need more than one connection. Otherwise, usually in one request, we're just dealing with one connection. So we just always assign it to db. So just be clear that the format of the connection string is database-specific. So this is an example with Postgres. This is what Postgres connection strings look like. For other databases, most of them look quite similar, but it's really up to each particular database. What you see here are the primary data types that effectively make up the DAO. First, there's the DAO type itself, which as we said represents a connection to the database. Then a table object represents a table within our schema. Be clear, it's not a table that was returned by a query. It's the actual table that makes up a data type within our database. As you'll see when we use the DAO to define a table within our database, the object we get back representing that table is of type table. And then within each table of our schema, each column is represented by a field object. I suppose they went with the term field because it's more generic than column. Column is a relational database-specific term, whereas field is a more general term. It doesn't seem as out of place when used in conjunction with a non-relational database like the Google App Engine.  And the part that's a bit confusing is what is called a query in Web2Py is not really the same as in SQL, because in SQL a query pretty much refers to just a select statement, whereas updates and deletes are not queries. The query object actually represents the part common to those three different statements. So in a select statement, update statement, and delete statement, you have the part where you're specifying the joining of the tables and then optionally you have where clauses and other kinds of clauses. Well, those parts are all common to those three different statements, so they're represented together in a single object called query. Once you have a query object, if you want to actually use it to perform a select, update, or delete, you first wrap it in another class called set, and then the set object has three methods, select, update, and delete. And those methods actually trigger the real action. When you define the query, that's just the preliminary stage of defining what kind of select, update, or delete you're going to do later. Now, you're probably wondering why do we wrap queries in set objects to actually perform these operations. And the answer is there isn't any particularly good reason. In fact, I went on the message board and I raised a discussion of, hey, why does this thing exist? Why is there a set class? Why do we have to wrap query objects in set objects? And the answer is that, well, it just, in retrospect, seems to have been a design mistake. The creator, Massimo, said that at some point he suggested to the others that we should change this, and they said, now let's just keep it. So I would argue, if you want to understand what does the set class do, why is it called set? Well, the justification given for that is that the set somehow represents the set of rows which would be selected by the query. It doesn't make sense, to be honest. It doesn't really make any sense. So the answer is the set class doesn't do anything. The query class itself should have had the methods select, update, and delete, as it is they don't. So you have to wrap them in the set object which has those methods. But that, again, was a design mistake. The query object itself should have those methods. So the oddity of that will be clear when we look at a bit of code. In any case, when you perform a query, when you perform a select, what you get back is an object of type rows, rows plural. And that, as the name applies, represents a set of rows. It's the data returned by the query. And a rows object is just a collection of row objects, and each row object represents a single row within that result set. Now, one important purpose of the whole database abstraction layer is that it abstracts over the variance in data types, because databases have their own number types, their own string types, their own date types, and so forth. But in Python, we want to deal with Python types. We want an integer in our Python code to be a Python integer. Also, the whole point with a DAO is that it abstracts over different backends. And different backends, different databases have different, say, integer types and different float types and different text types and so forth. So to deal with this problem, Python itself has to define its own data types for the columns of the tables. So, here's a list of most of those data types. First, string and text are what you use most commonly to store text data, and whereas a text value can be up to 65,536 characters long, string values only go up to 512 characters, though actually in the case of string you can specify a different length. That's just the default. For cases where you're trying to store text in 65,536 characters, for that we use a blob. The blob type is generally used to store file content, binary data, but there's no reason that binary data can't be text data. As for booleans, integers, and doubles, those should all be self-explanatory. The only thing to keep in mind is that integers and doubles are both constrained to the range of negative 1 times 10 to the power of 100 up to positive 1 times 10 to the 100th power. If, though, you need greater range and or precision, there's also a type called decimal, which we'll talk about in the supplement. And a datetime column, of course, stores a datetime value. In Python, these are expressed as Python datetime objects. And then finally we have reference fields, reference columns. A reference field is a foreign key to another table. So, for example, if I want my column to be a foreign key to the cat's table, it's space cat's. And this only works because the dial automatically gives every table automatically and implicitly a primary key column of type integer and with the name id. So, when you create a reference column, it's always an integer foreign key pointing to the primary key named id of some other table.