Exodus 5
1 Ref Afterward Moses and Aaron came, and said to Pharaoh, "This is what Yahweh, the God of Israel, says, 'Let my people go, that they may hold a feast to me in the wilderness.'"
2 Ref Pharaoh said, "Who is Yahweh, that I should listen to his voice to let Israel go? I don't know Yahweh, and moreover I will not let Israel go."