Exodus 7:2-5

2You must say everything that I command you to say. Your brother Aaron must tell Pharaoh to let the Israelites go out of his country.

3But I will make Pharaoh's mind become hard. I will do many miracles in Egypt that show my power.

4But Pharaoh will still refuse to listen to you. Then I will show my authority and I will punish the Egyptians. I will bring my people, the Israelites, out of Egypt like an army.

5Then the Egyptians will know that I am the Lord. I will show my great strength in Egypt and I will lead the Israelites out from there.’