Acts 7:30-36

And when forty years were fulfilled, an angel appeared to him in the wilderness of mount Sinai, in a flame of fire in a bush. And when Moses saw it, he wondered at the sight: and as he drew near to behold, there came a voice of the Lord, I am the God of thy fathers, the God of Abraham, and of Isaac, and of Jacob. And Moses trembled, and durst not behold. And the Lord said unto him, Loose the shoes from thy feet: for the place whereon thou standest is holy ground. I have surely seen the affliction of my people that is in Egypt, and have heard their groaning, and I am come down to deliver them: and now come, I will send thee into Egypt. This Moses whom they refused, saying, Who made thee a ruler and a judge? him hath God sent to be both a ruler and a deliverer with the hand of the angel that appeared to him in the bush. This man led them forth, having wrought wonders and signs in Egypt, and in the Red sea, and in the wilderness forty years.