Exodus 9:12 in the King James Version
And the LORD hardened the heart of Pharaoh, and he hearkened not unto them; as the LORD had spoken unto Moses.
Context
11 The magicians couldn’t stand before Moses because of the boils; for the boils were on the magicians and on all the Egyptians.
12 The LORD hardened the heart of Pharaoh, and he didn’t listen to them, as the LORD had spoken to Moses.
13 The LORD said to Moses, “Rise up early in the morning, and stand before Pharaoh, and tell him, ‘This is what the LORD, the God of the Hebrews, says: “Let my people go, that they may serve me.