What happensPermalink
God promises to harden Pharaoh’s heart to demonstrate His power. Aaron turns his staff into a serpent, and the Egyptian magicians copy it (but Aaron’s rod swallows theirs). God turns the Nile and all other water to blood, but the magicians copy that, too, so Pharaoh is not swayed.
Why it mattersPermalink
The turning of the water in wood and stone vessels makes any natural explanation of the plague of blood impossible: this was a miracle. The Nile is the lifeblood of Egypt, now incapable of giving life.
Key versePermalink
Moses and Aaron did as the Lord commanded. In the sight of Pharaoh and in the sight of his servants he lifted up the staff and struck the water in the Nile, and all the water in the Nile turned into blood.