Reference

Exodus 7:12

For they cast down every man his rod, and they became serpents: but Aaron’s rod swallowed up their rods.
10

And Moses and Aaron went in unto Pharaoh, and they did so as the Lord had commanded: and Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent.

11

Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments.

12

For they cast down every man his rod, and they became serpents: but Aaron’s rod swallowed up their rods.

13

And he hardened Pharaoh’s heart, that he hearkened not unto them; as the Lord had said.

14

And the Lord said unto Moses, Pharaoh’s heart is hardened, he refuseth to let the people go.