Exodus 9:35
So Pharaoh's heart remained hard, and he did not release the Israelites, as the Lord had predicted through Moses.
Exodus 4:21
The Lord said to Moses, "When you go back to Egypt, see that you do before Pharaoh all the wonders I have put under your control. But I will harden his heart and he will not let the people go.
Treasury of Scripture Knowledge
Summary
And the heart of Pharaoh was hardened, neither would he let the children of Israel go; as the LORD had spoken by Moses.
General references
Bible References
General references
Jeremiah 34:11
But later they had changed their minds. They had taken back their male and female slaves that they had freed and forced them to be slaves again.