Exodus 13:12-13

12That thou shall set apart to the LORD all that openeth the womb, and every firstling that cometh of a beast which thou hast; the males shall be the LORD’S.1 13And every firstling of a donkey 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.2