Exodus 4:4-6

New Century Version

⁴ but the Lord said to him, “Reach out and grab the snake by its tail.” When Moses reached out and took hold of the snake, it again became a stick in his hand. ⁵ The Lord said, “This is so that the Israelites will believe that the Lord appeared to you. I am the God of their ancestors, the God of Abraham, the God of Isaac, and the God of Jacob.”

⁶ Then the Lord said to Moses, “Put your hand inside your coat.” So Moses put his hand inside his coat. When he took it out, it was white with a skin disease.