Then the magicians of Egypt did so with their enchantments; and Pharaoh's heart grew hard, and he did not heed them, as the LORD had said.
Exodus 7:22
Surrounding context
7:21 The fish that were in the river died, the river stank, and the Egyptians could not drink the water of the river. So there was blood throughout all the land of Egypt.
7:22 Then the magicians of Egypt did so with their enchantments; and Pharaoh's heart grew hard, and he did not heed them, as the LORD had said.
7:23 And Pharaoh turned and went into his house. Neither was his heart moved by this.