Exodus.
Chapter 11.
Then the LORD said to Moses, “I will bring upon Pharaoh and Egypt one more plague. After that, he will allow you to leave this place. And when he lets you go, he will drive you out completely. 
Now announce to the people that men and women alike should ask their neighbors for articles of silver and gold.” 
And the LORD gave the people favor in the sight of the Egyptians. Moreover, Moses himself was highly regarded in Egypt by Pharaoh’s officials and by the people. 
So Moses declared, “This is what the LORD says: ‘About midnight I will go throughout Egypt, 
and every firstborn son in the land of Egypt will die, from the firstborn of Pharaoh who sits on his throne, to the firstborn of the servant girl behind the hand mill, as well as the firstborn of all the cattle. 
Then a great cry will go out over all the land of Egypt. Such an outcry has never been heard before and will never be heard again. 
But among all the Israelites, not even a dog will snarl at man or beast.’ Then you will know that the LORD makes a distinction between Egypt and Israel. 
And all these officials of yours will come and bow before me, saying, ‘Go, you and all the people who follow you!’ After that, I will depart.” And hot with anger, Moses left Pharaoh’s presence. 
The LORD said to Moses, “Pharaoh will not listen to you, so that My wonders may be multiplied in the land of Egypt.” 
Moses and Aaron did all these wonders before Pharaoh, but the LORD hardened Pharaoh’s heart so that he would not let the Israelites go out of his land. 
