Exodus 14:4-5

14:4 I will harden Pharaoh’s heart, and he will chase after them. I will gain honor because of Pharaoh and because of all his army, and the Egyptians will know that I am the Lord.” So this is what they did.

14:5 When it was reported to the king of Egypt that the people had fled, the heart of Pharaoh and his servants was turned against the people, and the king and his servants said, “What in the world have we done? For we have released the people of Israel from serving us!”