Exodus 7:22

The magicians of Egypt did so. Just as during Moses’ previous visit, the magicians were again consulted. Once more they counterfeited a genuine miracle by seeming to transform a certain quantity of water into blood. The question as to where the water the magicians used came from is answered in v. 24, which implies that newly dug wells furnished satisfactory drinking water. That the magicians actually turned the water into blood is not necessarily implied in the vague expression “did so.” They needed only to convince Pharaoh that they were able to do what Moses and Aaron had done. No critical examination was given their pretended miracle, which, in spite of being a trick, consequently passed as genuine. Had these men possessed the power they claimed to have they should have been able to turn the bloody water of the Nile back into normal water. That the king was satisfied with an imitation miracle shows stupidity, in his case probably the result of his hardened heart. He believed what he wanted to believe.