Exodus 11:7-9

7But against none of the children of Israel shall a dog move its tongue, against man or beast, that you may know that the Lord does make a difference between the Egyptians and Israel.’

8And all these your servants shall come down to me and bow down to me, saying, ‘Get out, and all the people who follow you!’ After that I will go out.” Then he went out from Pharaoh in great anger.

9But the Lord said to Moses, “Pharaoh will not heed you, so that My wonders may be multiplied in the land of Egypt.”