Parallel
Exodus 9:12
Brenton's English Septuagint · Berean Standard Bible
And the Lord hardened Pharao's heart, and he hearkened not to them, as the Lord appointed.
But the LORD hardened (note: Or stiffened or strengthened; also in verse 35) Pharaoh’s heart, and he would not listen to them, just as the LORD had said to Moses.