Exodus 8:10

8:10 He said, “Tomorrow.” And Moses said, “It will be as you say, so that you may know that there is no one like the Lord our God.

Exodus 8:22

8:22 But on that day I will mark off the land of Goshen, where my people are staying, so that no swarms of flies will be there, that you may know that I am the Lord in the midst of this land.