Exodus 11:1-5
English Standard Version
Chapter 11
1The Lord said to Moses, "Yet one plague more I will bring upon Pharaoh and upon Egypt. Afterward he will let you go from here. When he lets you go, he will drive you away completely. 2Speak now in the hearing of the people, that they ask, every man of his neighbor and every woman of her neighbor, for silver and gold jewelry." 3And the Lord gave the people favor in the sight of the Egyptians. Moreover, the man Moses was very great in the land of Egypt, in the sight of Pharaoh 's servants and in the sight of the people.
4So Moses said, "Thus says the Lord: ‘About midnight I will go out in the midst of Egypt,
5and every firstborn in the land of Egypt shall die, from the firstborn of Pharaoh who sits on his throne, even to the firstborn of the slave girl who is behind the handmill, and all the firstborn of the cattle.