Exodus 7
11 Ref Then Pharaoh sent for the wise men and the wonder-workers, and they, the wonder-workers of Egypt, did the same with their secret arts.
12 Ref For every one of them put down his rod on the earth, and they became snakes: but Aaron's rod made a meal of their rods.
13 Ref But Pharaoh's heart was made hard, and he did not give ear to them, as the Lord had said.