What does Exodus 7:10 mean?
Moses and Aaron are obeying the Lord's command (Exodus 7:8–9) to once again (Exodus 5:1–3) confront the Egyptian king, known by the title "Pharaoh." They are using one of the signs which God provided to prove the truth of their message (Exodus 4:2–4). Aaron's staff becomes a snake. Besides being a supernatural act, it also carries symbolism. Snakes are associated with evil and judgment (Genesis 3:1; 49:17; Numbers 21:6–9), so this implies that God's servants are prepared to deliver catastrophe to Egypt.Further symbolism comes after the Egyptian sorcerers seem to duplicate the feat (Exodus 7:11). But the serpent associated with God consumes the snakes of the Egyptian magicians. Whatever strength Pharaoh may think he has, it is helpless against the power of the Lord.
Nothing in Scripture suggests that Moses and Aaron are engaged in trickery or puppet work when changing the staff into a serpent. The purpose is to prove that the Lord is behind their message. This is also among the motives behind the upcoming plagues (Exodus 3:20; 6:6). This is a supernatural transformation of an actual staff into an actual snake. There is some debate as to whether the Egyptian version is also real, or an illusion, but there is no question that Israel's side of the contest is legitimate.