Verse 15: "When Pharaoh stubbornly refused to let us go, the Lord killed the firstborn of both people and animals in Egypt. This is why I sacrifice to the Lord the first male offspring of every womb and redeem each of my firstborn sons."
Exodus 13:1 - 22
ESV - 1 The Lord said to Moses. 2 "Consecrate to me all the firstborn. Whatever is the first to open the womb among the people of Israel, both of man and of beast, is mine."
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