Exodus 7:9-13

9When Pharaoh shall speak unto you, saying, Show a wonder for you; then thou shalt say unto Aaron, Take thy rod, and cast it down before Pharaoh, that it become a serpent. 10And Moses and Aaron went in unto Pharaoh, and they did so, as Jehovah had commanded: and Aaron cast down his rod before Pharaoh and before his servants, and it became a serpent. 11Then Pharaoh also called for the wise men and the sorcerers: and they also, the magicians of Egypt, did in like manner with their enchantments. 12For they cast down every man his rod, and they became serpents: but Aaron’s rod swallowed up their rods. 13And Pharaoh’s heart was hardened, and he hearkened not unto them; as Jehovah had spoken.