Exodus 3:10-12 NIV

[10] So now, go. I am sending you to Pharaoh to bring my people the Israelites out of Egypt.” [11] But Moses said to God, “Who am I that I should go to Pharaoh and bring the Israelites out of Egypt?” [12] And God said, “I will be with you. And this will be the sign to you that it is I who have sent you: When you have brought the people out of Egypt, you will worship God on this mountain.”