And he said, “Throw it on the ground.” So he threw it on the ground, and it became a serpent, and Moses ran from it.
Moses objects that the people will not believe him, yet God had promised they would hearken. His doubt does not square with God's word; past rejection made him fear the same again, though he was happily mistaken. The signs God appointed would convince them where bare word could not.
AI summary
Commenting on Exodus 4:1-9
And he said, cast it on the ground,.... That is, the rod or staff: and he cast it on the ground, and it became a serpent; not in appearance only, but in reality, it was changed into a real living serpent; for God, who is the author of nature, can change the nature of things as he pleases; nor is it to be supposed that...
A serpent - Of what sort we know not, as the word נחש nachash is a general name for serpents, and also means several other things, see Gen 3:1 : but it was either of a kind that he had not seen before, or one that he knew to be dangerous; for it is said, he fled from before it.