2.27 For what has originated, destruction is certain - it is seen to be inevitable. Similarly what has perished will inevitably originate. How should this be understood - that there is origination for that (entity)which has perished?  It is seen that an existing entity only can originate and not a non-existent one. Origination, annihilation etc., are merely particular states of an existent entity.

Now thread etc., do really exist. When arranged in a particular way, they are called clothes etc. It is seen that even those who uphold the doctrine that the effect is a new entity (Asatkarya-vadins) will admit this much that no new entity over and above the particular arrangement of threads is seen. It is not tenable to hold that this is the coming into being of a new entity, since, by the process of manufacture there is only attainment of a new name and special functions. No new entity emerges.

Origination, annihilation etc., are thus particular stages of an existent entity. With regard to an entity which has entered into a stage known as origination, its entry into the opposite condition is called annihilation. Of an evolving entity, a seqence of evolutionary stages is inevitable. For instance, clay becomes a lump, jug, a potsherd, and (finally) powder. Here, what is called annihilation is the attainment of a succeeding stage by an entity which existed previously in a preceding stage. And this annihilation itself is called birth in that stage. Thus, the seence called birth and annihilation being inevitable for an evolving entity, it is not worthy of you to grieve.

Now Sri Krsna says that not even the slightest grief arising from seeing an entity passing from a previous existing stage to an opposite stage, is justifiable in regard to human beings etc.