Exodus 8:22-27

And in that day I will set apart the land of Goshen, in which My people dwell, that no swarms of flies shall be there, in order that you may know that I am the LORD in the midst of the land. I will make a difference between My people and your people. Tomorrow this sign shall be.” ’ ” And the LORD did so. Thick swarms of flies came into the house of Pharaoh, into his servants’ houses, and into all the land of Egypt. The land was corrupted because of the swarms of flies. Then Pharaoh called for Moses and Aaron, and said, “Go, sacrifice to your God in the land.” And Moses said, “It is not right to do so, for we would be sacrificing the abomination of the Egyptians to the LORD our God. If we sacrifice the abomination of the Egyptians before their eyes, then will they not stone us? We will go three days’ journey into the wilderness and sacrifice to the LORD our God as He will command us.”