Exodus 9:10-12

New International Version - UK

¹⁰ So they took soot from a furnace and stood before Pharaoh. Moses tossed it into the air, and festering boils broke out on people and animals. ¹¹ The magicians could not stand before Moses because of the boils that were on them and on all the Egyptians. ¹² But the Lord hardened Pharaoh’s heart and he would not listen to Moses and Aaron, just as the Lord had said to Moses.