Leviticus

Sanctify unto me all the firstborn, whatsoever openeth the womb among the children of Israel, both of man and of beast: it is mine.

That thou shalt set apart unto the Lord all that openeth the matrix, and every firstling that cometh of a beast which thou hast; the males shall be the Lord’s.

And every firstling of an ass thou shalt redeem with a lamb; and if thou wilt not redeem it, then thou shalt break his neck: and all the firstborn of man among thy children shalt thou redeem.

All the firstling males that come of thy herd and of thy flock thou shalt sanctify unto the Lord thy God: thou shalt do no work with the firstling of thy bullock, nor shear the firstling of thy sheep.

But the firstling of a cow, or the firstling of a sheep, or the firstling of a goat, thou shalt not redeem; they are holy: thou shalt sprinkle their blood upon the altar, and shalt burn their fat for an offering made by fire, for a sweet savour unto the Lord.