Exodus 9:10-12

American Standard Version

¹⁰ And they took ashes of the furnace, and stood before Pharaoh; and Moses sprinkled it up toward heaven; and it became a boil breaking forth with blains upon man and upon beast. ¹¹ And the magicians could not stand before Moses because of the boils; for the boils were upon the magicians, and upon all the Egyptians. ¹² And Jehovah ^[a]hardened the heart of Pharaoh, and he hearkened not unto them; as Jehovah had spoken unto Moses.