Exodus 4:1-4

Then Moses answered, “What if the people of Israel do not believe me or listen to me? What if they say, ‘The Lord did not appear to you’?” The Lord said to him, “What is that in your hand?” Moses answered, “It is my walking stick.” The Lord said, “Throw it on the ground.” So Moses threw it on the ground. And it became a snake. Moses ran from the snake. But the Lord said to him, “Reach out and grab the snake by its tail.” So Moses reached out and took hold of the snake. When he did this, it again became a stick in his hand.