When Pharaoh persisted in his refusal to liberate the children of Israel, Moses and Aaron warned him that G-d would punish both him and his people. First, the waters of the land of Egypt were to be turned into blood.

Moses walked with Aaron to the brink of the river. There Aaron raised his staff, smote the water, and converted them into streams of blood. All the people of Egypt and the King himself beheld this miracle; they saw the fish die as the blood flowed over the land, and they turned with disgust from the offensive smell of the sacred river.

It was impossible for them to drink of the water of the Nile, far famed for its delicious taste; and they tried to dig deep into the ground for water. Unfortunately for the Egyptians, not only the floods of the Nile but all the waters of Egypt, wherever they were, turned to blood. The fish died in the rivers and lakes, and for a whole week man and beast suffered horrible thirst.

Yet Pharaoh would not give in.