 Medea also asked the hero to swear to have her to become his wife and would take her with him on the voyage to Greece.When Jason swore to do so, she aid him to be freed from all danger, for she gave him a drug with which she bade him anoint his shield, spear, and body when he was about to yoke the bulls; for she said that, anointed with it, he could for a single day be harmed neither by fire nor by iron.And she signified to him that, when the teeth were sown, armed men would spring up from the ground against him; and when he saw a knot of them he was to throw stones into their midst from a distance, and when they fought each other about that, he was taken to kill them.