Next the LORD told Moses, "Get up early in the morning and meet Pharaoh as he goes down to the river. Say to him, 'This is what the LORD says: Let my people go, so they can worship me.
If you refuse, I will send swarms of flies throughout Egypt. Your homes will be filled with them, and the ground will be covered with them.
But it will be very different in the land of Goshen, where the Israelites live. No flies will be found there. Then you will know that I am the LORD and that I have power even in the heart of your land.
I will make a clear distinction between your people and my people. This miraculous sign will happen tomorrow.'"
And the LORD did just as he had said. There were terrible swarms of flies in Pharaoh's palace and in every home in Egypt. The whole country was thrown into chaos by the flies.
Pharaoh hastily called for Moses and Aaron. "All right! Go ahead and offer sacrifices to your God," he said. "But do it here in this land. Don't go out into the wilderness."
But Moses replied, "That won't do! The Egyptians would detest the sacrifices that we offer to the LORD our God. If we offer them here where they can see us, they will be sure to stone us.
We must take a three-day trip into the wilderness to offer sacrifices to the LORD our God, just as he has commanded us."
"All right, go ahead," Pharaoh replied. "I will let you go to offer sacrifices to the LORD your God in the wilderness. But don't go too far away. Now hurry, and pray for me."
"As soon as I go," Moses said, "I will ask the LORD to cause the swarms of flies to disappear from you and all your people. But I am warning you, don't change your mind again and refuse to let the people go to sacrifice to the LORD."
So Moses left Pharaoh and asked the LORD to remove all the flies.
And the LORD did as Moses asked and caused the swarms to disappear. Not a single fly remained in the land!
But Pharaoh hardened his heart again and refused to let the people go.