And Moses and Aaron went in unto Pharaoh, and they did so as the LORD had commanded: and Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent.
All Commentaries on Exodus 7:10 Go To Exodus 7
Augustine of Hippo
AD 430
For by the serpent is to be understood death, which was brought about by the serpent in paradise, according to the manner of speech which attributes the effect to the cause. Therefore the rod was turned into a serpent, and the whole Christ, together with his body which is the church, into the resurrection, that will take place at the end of time. This is signified by the tail of the serpent which Moses held, in order that it might be turned again into a rod. But the serpents of the magicians are like those who are dead in the world, for, unless by believing in Christ they have been as it were swallowed up and entered into his body, they will not be able to rise in him.