How are we to determine who was responsible for Pharaoh’s stubborn refusal to let the Hebrew people go free? On the one hand, we are told that it was God who hardened Pharaoh’s heart (Exodus 7.3; 9.12; 10.1, 20, 27; 11.10). Other passages report that Pharaoh hardened his own heart (Exodus 8.15, 32; 9.34).
The author of Exodus makes no attempt to harmonize these two viewpoints. What we have here is an illustration of the paradox of human freedom and divine sovereignty. While Pharaoh was a free moral agent pursuing his own course of action and fully responsible for his own behavior, God still maintained ultimate control over the situation. It was God and not Pharaoh who would determine the outcome. Pharaoh was given plenty of rope, but the end of the rope was still held firmly in the hand of God.
Paul understood God’s reason for putting up with Pharaoh’s stubbornness when he wrote:
What shall we say then? There is no injustice with God, is there? May it never be! For He says to Moses, “I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.” So then it does not depend on the man who wills or the man who runs, but on God who has mercy. For the Scripture says to Pharaoh, “For this very purpose I raised you up, to demonstrate My power in you, and that My name might be proclaimed throughout the whole earth.” So then He has mercy on whom He desires, and He hardens whom He desires (Romans 9.14-18).