[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 the LORD, Let my people go, that they may serve [21] Else, if thou wilt not let my people go, swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: shall be full of swarms of flies, and also the ground whereon they are.