Exodus 9:10

7 and Pharaoh sendeth, and lo, not even one of the cattle of Israel hath died, and the heart of Pharaoh is hard, and he hath not sent the people away.

8 And Jehovah saith unto Moses and unto Aaron, `Take to you the fulness of your hands [of] soot of a furnace, and Moses hath sprinkled it towards the heavens, before the eyes of Pharaoh,

9 and it hath become small dust over all the land of Egypt, and it hath become on man and on cattle a boil breaking forth [with] blains, in all the land of Egypt.`

10 And they take the soot of the furnace, and stand before Pharaoh, and Moses sprinkleth it towards the heavens, and it is a boil [with] blains, breaking forth, on man and on beast;

11 and the scribes have not been able to stand before Moses, because of the boil, for the boil hath been on the scribes, and on all the Egyptians.

12 And Jehovah strengtheneth the heart of Pharaoh, and he hath not hearkened unto them, as Jehovah hath spoken unto Moses.

13 And Jehovah saith unto Moses, `Rise early in the morning, and station thyself before Pharaoh, and thou hast said unto him, Thus said Jehovah, God of the Hebrews, Send My people away, and they serve Me,