Pharaoh has just witnessed the authority of Moses’ and Aaron’s God. Aaron’s staff became a serpent and swallowed the sorcerers’ staffs. Still, his heart was hardened. Now, the Lord instructs Moses and Aaron to go back to Pharaoh, remind him of his disobedience, and bring a plague to the land of Egypt.
Moses and Aaron obeyed God. They turned the water of the Nile River and all of Egypt into blood. All the fish died. The Egyptians had no water to drink. Blood was everywhere.
Somehow, Pharaoh still refused to listen. The magicians turned water into blood, too. If they had wanted to show real power, maybe they should have practiced turning blood back into water. But they could not. Seven days the blood remained.
The reason? God is so good that he tells Pharaoh the reason he is turning the water into blood. God said that, “By this you shall know that I am the Lord.”
God was proving his authority over all the world once again. Why blood though?
The very sight of blood should be alarming to a creature whose life depends on it. God is saying, “You are human, Pharaoh; mere flesh and blood. I am God; listen to me.” Furthermore, blood is about life – and death – over which God alone has ultimate control. God is both the giver as well as the taker of life. Pharaoh did not give these Jews life – God did. Pharaoh did not give himself life – God did. God shows Pharaoh his power using blood that he might know not only his power and authority, but also his entitlement to all life. In other words, God made the Jews; give the Jews back to God. God made you; obey him.
Despite the miracle of this first plaque on Egypt, Pharaoh still did not obey.