1 And the I AM said to Moses, “Yet will I bring one plague more on Pharaoh, and on Egypt. Afterwards he will let you go from here. When he shall let you go, he drive you out altogether.
“He’s not only going to let you go worship Me, Pharaoh will kick you out of the country.”
2 “Speak now in the ears of the people, and let every man borrow of his neighbor, and every woman of her neighbor, jewels of silver and jewels of gold.”
Israel had served Egypt a long time without proper wages. Plus, the loss of so many sons being thrown into the river must be paid for. God arranges for this payment.
3 And the I AM 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.
God caused people to admire Moses. It didn’t really matter how well Moses spoke or what he looked like or how much money he had, like we humans tend to think. If God wants you known and admired, you will be known and admired.
4 And Moses said, “This is what the I AM says, ‘About midnight will I go out into the middle of Egypt:
5 “ ‘And all the firstborn in the land of Egypt shall die, from the first born of Pharaoh that sits on his throne, even to the firstborn of the maidservant that is behind the mill; and all the firstborn of animals.’
God had promised in Exodus 3 that He would have to kill Pharaoh’s son. Now the time has come.
6 “And there shall be a great cry throughout all the land of Egypt, such as there has never been before, nor will be like it again.
7 “But against any of the children of Israel shall not a dog move his tongue, against man or beast: that ye may know how that the I AM does put a difference between the Egyptians and Israel.
8 “And all these thy servants shall come down to me, and bow down themselves to me, saying, ‘Get thee out, and all the people that follow thee:’ and after that I will go out.” And he went out from Pharaoh in a great anger.
I don’t know what happened to Moses and Pharaoh both agreeing to not see each other again. Maybe Moses went to the palace and sent a message in to him. Or maybe Moses actually said this after agreeing to never see Pharaoh again but before leaving the room.
Anyway, Pharaoh has been duly warned.
9 And the I AM said to Moses, “Pharaoh will not listen to you, so My wonders may be multiplied in the land of Egypt.”
10 And Moses and Aaron did all these wonders before Pharaoh. And the I AM hardened Pharaoh's heart, so that he would not let the children of Israel go out of his land.