Exodus 7:13

Yet Pharaoh's heart became hard and he would not listen to them, just as the LORD had said.

(New International Version)

Yet Pharaoh's heart was hardened, and he did not listen to them, as the LORD had said.

(New American Standard Bible)

And he hardened Pharaoh's heart, that he hearkened not unto them; as the LORD had said.

(King James Version)