'Dust of the Ground' in the Bible

Then the Lord said to Moses, “Say to Aaron, ‘Stretch out your staff and strike the dust of the ground, and it will become [biting] gnats (lice) throughout the land of Egypt.’”

They did this. Aaron stretched his hand out with his staff, struck the dust of the land, and gnats came on people and animals all the dust of the ground became gnats throughout the land of Egypt.