King James Version (KJV) Authorized Version 1611
Read Full Chapter (Exodus 8)

Exodus 8:21-22 KJV

"Else, if thou wilt not let my people go, behold, I will send swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: and the houses of the Egyptians shall be full of swarms of flies, and also the ground whereon they are. And I will sever in that day the land of Goshen, in which my people dwell, that no swarms of flies shall be there; to the end thou mayest know that I am the LORD in the midst of the earth."
Exodus Chapter 8, Verse 21-22

Exodus 8:21-22 in Context (Verses 18–25 KJV)

18
And the magicians did so with their enchantments to bring forth lice, but they could not: so there were lice upon man, and upon beast.
19
Then the magicians said unto Pharaoh, This is the finger of God: and Pharaoh’s heart was hardened, and he hearkened not unto them; as the LORD had said.
20
¶ And the LORD said unto Moses, Rise up early in the morning, and stand before Pharaoh; lo, he cometh forth to the water; and say unto him, Thus saith the LORD, Let my people go, that they may serve me.
21
Else, if thou wilt not let my people go, behold, I will send swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: and the houses of the Egyptians shall be full of swarms of flies, and also the ground whereon they are.*
22
And I will sever in that day the land of Goshen, in which my people dwell, that no swarms of flies shall be there; to the end thou mayest know that I am the LORD in the midst of the earth.
23
And I will put a division between my people and thy people: to morrow shall this sign be.**
24
And the LORD did so; and there came a grievous swarm of flies into the house of Pharaoh, and into his servants’ houses, and into all the land of Egypt: the land was corrupted by reason of the swarm of flies.*
25
¶ And Pharaoh called for Moses and for Aaron, and said, Go ye, sacrifice to your God in the land.