Yahweh said to Moses, "Behold, I have made you as God to Pharaoh; and Aaron your brother shall be your prophet.
You shall speak all that I command you; and Aaron your brother shall speak to Pharaoh, that he let the children of Israel go out of his land.
I will harden Pharaoh's heart, and multiply my signs and my wonders in the land of Egypt.
But Pharaoh will not listen to you, and I will lay my hand on Egypt, and bring forth my hosts, my people the children of Israel, out of the land of Egypt by great judgments.
The Egyptians shall know that I am Yahweh, when I stretch forth my hand on Egypt, and bring out the children of Israel from among them."
Moses and Aaron did so. As Yahweh commanded them, so they did.