Exodus 3:10-12

So now, go. I am sending you to Pharaoh to bring my people the Israelites out of Egypt.’ But Moses said to God, ‘Who am I that I should go to Pharaoh and bring the Israelites out of Egypt?’ 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.’