Then the Lord said to Moses and Aaron, “Take for yourselves handfuls of soot from a kiln, and let Moses throw it toward the sky in the sight of Pharaoh. It will become fine dust over all the land of Egypt, and will become boils breaking out with sores on man and beast through all the land of Egypt.” So they took soot from a kiln, and stood before Pharaoh; and Moses threw it toward the sky, and it became boils breaking out with sores on man and beast. The magicians could not stand before Moses because of the boils, for the boils were on the magicians as well as on all the Egyptians. And the Lord hardened Pharaoh’s heart, and he did not listen to them, just as the Lord had spoken to Moses.
Then the Lord said to Moses, “Rise up early in the morning and stand before Pharaoh and say to him, ‘Thus says the Lord, the God of the Hebrews, “Let My people go, that they may serve Me. For this time I will send all My plagues on you and your servants and your people, so that you may know that there is no one like Me in all the earth. For if by now I had put forth My hand and struck you and your people with pestilence, you would then have been cut off from the earth. But, indeed, for this reason I have allowed you to remain, in order to show you My power and in order to proclaim My name through all the earth.Still you exalt yourself against My people by not letting them go.