Exodus 10:1-3

Then the Lord said to Moses, “Go to Pharaoh, for I have hardened his heart and the heart of his servants, so that I may perform these signs of Mine among them,

and that you may tell in the presence of your son, and of your grandson, how I made a mockery of the Egyptians and how I performed My signs among them, so that you may know that I am the Lord.”

So Moses and Aaron went to Pharaoh and said to him, “This is what the Lord, the God of the Hebrews says: ‘How long will you refuse to humble yourself before Me? Let My people go, so that they may serve Me.