Exodus 7:5-15 ASV

5 And the Egyptians shall know that I am Jehovah, when I stretch forth my hand upon Egypt, and bring out the children of Israel from among them.
6 And Moses and Aaron did so; as Jehovah commanded them, so did they.
7 And Moses was fourscore years old, and Aaron fourscore and three years old, when they spake unto Pharaoh.
8 And Jehovah spake unto Moses and unto Aaron, saying,
9 When 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.
10 And 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.
11 Then Pharaoh also called for the wise men and the sorcerers: and they also, the magicians of Egypt, 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 Pharaoh's heart was hardened, and he hearkened not unto them; as Jehovah had spoken.
14 And Jehovah said unto Moses, Pharaoh's heart is stubborn, he refuseth to let the people go.
15 Get thee unto Pharaoh in the morning; lo, he goeth out unto the water; and thou shalt stand by the river's brink to meet him; and the rod which was turned to a serpent shalt thou take in thy hand.