Exodus 34:18-20

Darby Translation

¹⁸ —The feast of the unleavened bread shalt thou keep: seven days shalt thou eat unleavened bread, as I have commanded thee, at the appointed time of the month Abib; for in the month Abib thou camest out from Egypt.

¹⁹ —All that openeth the womb [is] mine; and all the cattle that is born a male, the firstling of ox and sheep.

²⁰ But the firstling of an ass thou shalt ransom with a lamb; and if thou ransom [it] not, then shalt thou break its neck. All the first-born of thy sons thou shalt ransom; and none shall appear before me empty.