Every firstborn of a donkey you shall redeem with a lamb; and if you will not redeem it, then you shall break its neck; and you shall redeem all the firstborn of man among your sons.
and it happened, when Par`oh would hardly let us go, that the LORD killed all the firstborn in the land of Egypt, both the firstborn of man, and the firstborn of animal. Therefore I sacrifice to the LORD all that opens the womb, being males; but all the firstborn of my sons I redeem.'