Sh'mot (Exo) 7:14-25

ADONAI said to Moshe, “Pharaoh is stubborn. He refuses to let the people go. Go to Pharaoh in the morning when he goes out to the water. Stand on the riverbank to confront him, take in your hand the staff which was turned into a snake, and say to him, ‘ADONAI, the God of the Hebrews, sent me to you to say: “Let my people go, so that they can worship me in the desert.” But until now you haven’t listened; so ADONAI says, “This will let you know that I am ADONAI”: I will take the staff in my hand and strike the water in the river, and it will be turned into blood. The fish in the river will die, the river will stink and the Egyptians won’t want to drink water from the river.’” ADONAI said to Moshe, “Say to Aharon, ‘Take your staff, reach out your hand over the waters of Egypt, over their rivers, canals, ponds and all their reservoirs, so that they can turn into blood. There will be blood throughout the whole land of Egypt, even in the wooden buckets and stone jars.’” Moshe and Aharon did exactly what ADONAI had ordered. He raised the staff and, in the sight of Pharaoh and his servants, struck the water in the river; and all the water in the river was turned into blood. The fish in the river died, and the river stank so badly that the Egyptians couldn’t drink its water. There was blood throughout all the land of Egypt. But the magicians of Egypt did the same with their secret arts, so that Pharaoh was made hardhearted and didn’t listen to them, as ADONAI had said would happen. Pharaoh just turned and went back to his palace, without taking any of this to heart. All the Egyptians dug around the river for water to drink, because they couldn’t drink the river water. Seven days after ADONAI had struck the river