Exodus 8:21-23

New International Version - UK

²¹ If you do not let my people go, I will send swarms of flies on you and your officials, on your people and into your houses. The houses of the Egyptians will be full of flies; even the ground will be covered with them.

²² ‘“But on that day I will deal differently with the land of Goshen, where my people live; no swarms of flies will be there, so that you will know that I, the Lord, am in this land. ²³ I will make a distinction^[a] between my people and your people. This sign will occur tomorrow.”’