It is remarkable that upon several occasions in scripture, for the confirmation of the faith and the confutation of error, the serpent is made use of, see Numbers 21:8. And it is yet more remarkable that this is expressly spoken of by the Redeemer himself as typical of his salvation. John 3:14.
Related Commentaries of Exodus 7:8
Exodus 7:8-9
8 And the LORD spake unto Moses and unto Aaron, saying,
9 When Pharaoh shall speak unto you, saying, Shew a miracle for you: then thou shalt say unto Aaron, Take thy rod, and cast it before Pharaoh, and it shall become a serpent.