Exodus 10:21-29

Then the LORD said to Moses, “Stretch out your hand toward the sky so that darkness spreads over Egypt—darkness that can be felt.” So Moses stretched out his hand toward the sky, and total darkness covered all Egypt for three days. No one could see anyone else or move about for three days. Yet all the Israelites had light in the places where they lived. Then Pharaoh summoned Moses and said, “Go, worship the LORD. Even your women and children may go with you; only leave your flocks and herds behind.” But Moses said, “You must allow us to have sacrifices and burnt offerings to present to the LORD our God. Our livestock too must go with us; not a hoof is to be left behind. We have to use some of them in worshiping the LORD our God, and until we get there we will not know what we are to use to worship the LORD.” But the LORD hardened Pharaoh’s heart, and he was not willing to let them go. Pharaoh said to Moses, “Get out of my sight! Make sure you do not appear before me again! The day you see my face you will die.” “Just as you say,” Moses replied. “I will never appear before you again.”