Exodus 12:12-13, 29-30

“I will go through the land of Egypt on this night and strike down every firstborn in the land of Egypt, whether human or animal, and bring judgment on all the gods of Egypt. I am GOD. The blood will serve as a sign on the houses where you live. When I see the blood I will pass over you—no disaster will touch you when I strike the land of Egypt.

At midnight GOD struck every firstborn in the land of Egypt, from the firstborn of Pharaoh, who sits on his throne, right down to the firstborn of the prisoner locked up in jail. Also the firstborn of the animals. Pharaoh got up that night, he and all his servants and everyone else in Egypt—what wild wailing and lament in Egypt! There wasn’t a house in which someone wasn’t dead.