The Bible
Exodus 3
The Lord appears to Moses at the burning bush—Moses is called to deliver Israel from bondage—The Lord identifies Himself as the God of Abraham, Isaac, and Jacob, and as the Great I Am—He promises to smite Egypt and bring His people out with great wealth.
3And Moses said, I will now turn aside, and see this great sight, why the bush is not burnt.

19¶ And I am sure that the king of Egypt will not let you go, no, not by a mighty hand.