14 The Lord said to Moses, “Pharaoh’s heart is stubborn. He refuses to let the people go.
15 Go to Pharaoh in the morning. Behold, he goes out to the water; and you shall stand by the river’s bank to meet him; and the rod which was turned to a serpent you shall take in your hand.
16 You shall tell him, ‘The Lord, the God of the Hebrews, has sent me to you, saying, “Let my people go, that they may serve me in the wilderness;” and behold, until now you haven’t listened.
17 the Lord says, “In this you shall know that I am the Lord. Behold: I will strike with the rod that is in my hand on the waters which are in the river, and they shall be turned to blood.
18 The fish that are in the river shall die, and the river shall become foul; and the Egyptians shall loathe to drink water from the river.”’”
19 The Lord said to Moses, “Tell Aaron, ‘Take your rod, and stretch out your hand over the waters of Egypt, over their rivers, over their streams, and over their pools, and over all their ponds of water, that they may become blood; and there shall be blood throughout all the land of Egypt, both in vessels of wood and in vessels of stone.’”
20 Moses and Aaron did so, as the Lord commanded; and he lifted up the rod, and struck the waters that were in the river, in the sight of Pharaoh, and in the sight of his servants; and all the waters that were in the river were turned to blood.