Exodus 11:9-10

New Revised Standard Version, Anglicised

⁹ The Lord said to Moses, ‘Pharaoh will not listen to you, in order that my wonders may be multiplied in the land of Egypt.’ ¹⁰ Moses and Aaron performed all these wonders before Pharaoh; but the Lord hardened Pharaoh’s heart, and he did not let the people of Israel go out of his land.