Exodus 3:9-12

And now, behold, the cry of the people of Israel has come to me, and I have also seen the oppression with which the Egyptians oppress them. Come, I will send you to Pharaoh that you may bring my people, the children of Israel, out of Egypt.” But Moses said to God, “Who am I that I should go to Pharaoh and bring the children of Israel out of Egypt?” He said, “But I will be with you, and this shall be the sign for you, that I have sent you: when you have brought the people out of Egypt, you shall serve God on this mountain.”