Exodus 3:10-12

Now go, for I am sending you to Pharaoh. You must lead my people Israel out of Egypt.” But Moses protested to God, “Who am I to appear before Pharaoh? Who am I to lead the people of Israel out of Egypt?” God answered, “I will be with you. And this is your sign that I am the one who has sent you: When you have brought the people out of Egypt, you will worship God at this very mountain.”