Exodus 4:3
And he said, Cast it on the ground. And he cast it on the ground, and it became a serpent; and Moses fled from before it.
Cross-reference
Exodus 4:17
Parallel
Exodus 4:17 refers back to the staff that became a serpent, now commissioned for signs.
Exodus 7:10–15
Prophetic fulfillment
Exodus 7:10-15 fulfills this sign as Aaron's staff becomes a serpent before Pharaoh.