Exodus 7:8

The Egyptians shall know that I am the LORD when I stretch out my hand on Egypt, and bring the children of Israel out from among them.”

Moses and Aaron did so. As the LORD commanded them, so they did.

Moses was eighty years old, and Aaron eighty-three years old, when they spoke to Pharaoh.

“When Pharaoh speaks to you, saying, ‘Perform a miracle!’ then you shall tell Aaron, ‘Take your rod, and cast it down before Pharaoh, and it will become a serpent.’”

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

Then Pharaoh also called for the wise men and the sorcerers. They also, the magicians of Egypt, did the same thing with their enchantments.