Exodus 7:1-9

The LORD said to Moses, “I have made you like God to the king of Egypt, and your brother Aaron will be like a prophet for you. Tell Aaron your brother everything that I command you, and let him tell the king of Egypt to let the Israelites leave his country. But I will make the king stubborn. I will do many miracles in Egypt, but he will still refuse to listen. So then I will punish Egypt terribly, and I will lead my divisions, my people the Israelites, out of that land. I will punish Egypt with my power, and I will bring the Israelites out of that land. Then they will know I am the LORD.” Moses and Aaron did just as the LORD had commanded them. Moses was eighty years old and Aaron was eighty-three when they spoke to the king. The LORD said to Moses and Aaron, “Moses, when the king asks you to do a miracle, tell Aaron to throw his walking stick down in front of the king, and it will become a snake.”