15 Then Pharaoh, seeing that relief had been provided, hardened his own heart, and he did not listen to them, just as the Lord had instructed.
16 And the Lord said to Moses: "Say to Aaron: 'Extend your staff and strike the dust of the earth. And let there be stinging insects throughout the entire the land of Egypt.' "
17 And they did so. And Aaron extended his hand, holding the staff, and he struck the dust of the earth, and there came stinging insects upon men and upon beasts. All the dust of the earth was turned into stinging insects through all the land of Egypt.
18 And the sorcerers, with their incantations, did similarly, in order to bring forth stinging insects, but they were not able. And there were stinging insects, as much on men as on beasts.
19 And the sorcerers said to Pharaoh: "This is the finger of God." And the heart of Pharaoh was hardened, and he did not listen to them, just as the Lord had instructed.
20 The Lord also said to Moses: "Arise at first light, and stand in the sight of Pharaoh, for he will go out to the waters. And you will say to him: 'Thus says the Lord: Release my people to sacrifice to me.
21 But if you will not release them, behold, I will send upon you, and upon your servants, and upon your people, and into your houses, diverse kinds of flies. And the houses of the Egyptians will be filled with diverse kinds of flies, as well as the whole land in which they will be.