Moses kept the flock of Jethro his father-in-law, the priest of Midian. (Called Reuel in Exodus 2)
Moses was forty years old when he left Egypt and the palace of Pharaoh. (Acts 7:23) And he had been in the land of Midian forty years. (Acts 7:30) Now he is eighty years old.
Moses led the flock to the backside of the desert and came to Horeb the mountain of God. And the angel of the Lord appeared to him in a flame of fire out of the midst of a bush. And he looked, and saw that the bush burned with fire, and yet the bush was not consumed.
Moses: I will now turn aside, and see this great sight, why the bush is not burnt.
And when the Lord saw that he turned aside to see, God called to him out of the midst of the bush.
God: Moses, Moses.
Moses: Here am I.
God: Do not come near here: put off your shoes from off your feet, for the place on which you stand is holy ground. I am the God of your father, the God of Abraham, the God of Isaac, and the God of Jacob.
And Moses hid his face; because he was afraid to look on God.
The Lord: I have seen the affliction of my people which are in Egypt. I have heard their cry by reason of their taskmasters; for I know their sorrows; And I am come down to deliver them out of the hand of the Egyptians, and to bring them up out of that land to a good land and a large land, to a land flowing with milk and honey; to the place of the Canaanites, and the Hittites, and the Amorites, and the Perizzites, and the Hivites, and the Jebusites. The cry of the children of Israel is come to me: and I have also seen the oppression with which the Egyptians oppress them. Comes and I will send you to Pharaoh, that you may bring my people, the children of Israel, out of Egypt.
Moses: Who am I, that I should go to Pharaoh, and that I should bring the children of Israel out of Egypt?
God: Certainly I will be with you; and this shall be a token for you, that I have sent you: When you have brought the people out of Egypt, you shall serve God on this mountain.
Moses: When I come to the children of Israel, and shall say to them, The God of your fathers has sent me to you; and they shall say to me, What is his name? What shall I say to them?
God: I Am that I Am: You shall say this to the children of Israel, I Am has sent me to you. You shall say this to the children of Israel, The Lord God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you: this is my name for ever, and this is my memorial to all generations. Go and gather the elders of Israel together, and say to them, The Lord God of your fathers, the God of Abraham, of Isaac, and of Jacob, appeared to me, saying, I have surely visited you, and seen that which is done to you in Egypt: And I have said, I will bring you up out of the affliction of Egypt to the land of the Canaanites, and the Hittites, and the Amorites, and the Perizzites, and the Hivites, and the Jebusites, to a land flowing with milk and honey. And they shall listen to your voice: and you shall come, you and the elders of Israel, to the king of Egypt, and you shall say to him, The Lord God of the Hebrews has met with us: and now let us go, we beseech you, three days’ journey into the wilderness, that we may sacrifice to the Lord our God. And I am sure that the king of Egypt will not let you go, no, not by a mighty hand. And I will stretch out my hand and strike Egypt with all my wonders which I will do in the middle of it. After that he will let you go. And I will give this people favor in the sight of the Egyptians: and when you go, you shall not go empty: But every woman shall borrow of her neighbor, and of her that sojourns in her house, jewels of silver, and jewels of gold, and garments. And you shall put them on your sons, and on your daughters; and you shall spoil the Egyptians.