Exodus 5:1-2

After this presentation to Israel’s leaders, Moses and Aaron went and spoke to Pharaoh. They told him, “This is what the LORD, the God of Israel, says: Let my people go so they may hold a festival in my honor in the wilderness.” “Is that so?” retorted Pharaoh. “And who is the LORD? Why should I listen to him and let Israel go? I don’t know the LORD, and I will not let Israel go.”