Exodus 8:20-24

20Now the Lord said to Moses, “Get up early in the morning and stand before Pharaoh as he is coming out to the water [of the Nile], and say to him, ‘Thus says the Lord, “Let My people go, so that they may serve Me.

21For if you do not let My people go, hear this: I will send swarms of [bloodsucking] insects on you and on your servants and on your people and into your houses; and the houses of the Egyptians will be full of swarms of insects, as well as the ground on which they stand.

22But on that day I will separate and set apart the land of Goshen, where My people are living, so that no swarms of insects will be there, so that you may know [without any doubt] and acknowledge that I, the Lord, am in the midst of the earth.

23I will put a division (distinction) between My people and your people. By tomorrow this sign shall be in evidence.” ’ ”

24Then the Lord did so. And there came heavy and oppressive swarms of [bloodsucking] insects into the house of Pharaoh and his servants’ houses; in all the land of Egypt the land was corrupted and ruined because of the [great invasion of] insects.