7. Moses was eighty years old, and Aaron eighty-three, when they spoke to Pharaoh.
8. The Lord spoke to Moses and Aaron:
9. When Pharaoh demands of you, “Produce a sign or wonder,” you will say to Aaron: “Take your staff and throw it down before Pharaoh, and it will turn into a serpent.”
10. Then Moses and Aaron went to Pharaoh and did just as the Lord had commanded. Aaron threw his staff down before Pharaoh and his servants, and it turned into a serpent.
11. Pharaoh, in turn, summoned the wise men and the sorcerers, and they also, the magicians of Egypt, did the same thing by their magic arts.
12. Each one threw down his staff, and they turned into serpents. But Aaron’s staff swallowed their staffs.
13. Pharaoh, however, hardened his heart and would not listen to them, just as the Lord had foretold.
14. Then the Lord said to Moses: Pharaoh is obstinate in refusing to let the people go.
15. In the morning, just when he sets out for the water, go to Pharaoh and present yourself by the bank of the Nile, holding in your hand the staff that turned into a snake.
16. Say to him: The Lord, the God of the Hebrews, sent me to you with the message: Let my people go to serve me in the wilderness. But as yet you have not listened.
17. Thus says the Lord: This is how you will know that I am the Lord. With the staff here in my hand, I will strike the water in the Nile and it will be changed into blood.
18. The fish in the Nile will die, and the Nile itself will stink so that the Egyptians will be unable to drink water from the Nile.