Exodus 9:13-14

Then the LORD said to Moses, “Get up early in the morning, confront Pharaoh and say to him, ‘This is what the LORD, the God of the Hebrews, says: Let my people go, so that they may worship me, or this time I will send the full force of my plagues against you and against your officials and your people, so you may know that there is no one like me in all the earth.