Does God harden the human heart? This question has been asked in reference to Romans 9:18 where we read: “So then He has mercy on whom He desire, and He hardens whom He desires.”
As we look at this passage in its context, we discover that it has nothing to do with an individual’s salvation. Nor can we interpret this passage in a way that removes a person’s free moral agency. The question raised in verse 19 sheds light on the meaning of the passage. Paul writes, “You will say to me then, ‘Why does He still find fault? For who resists His will?’” If the mercy discussed in this passage made it easier for one person to be saved than another, then one might argue: “Why does He still find fault?” Similarly, if the hardening discussed applied indiscriminately to one person and not to another, one could still argue: “Why does He still find fault?” In other words, our salvation would have nothing to do with our faith response. That position violates other clearer passages of Scripture (Acts 10:34-35; Eph. 2:8-9; Hb. 11:6).
So, in what sense does God show mercy on whom He desires and hardens others whom He desires? In the context, two examples are given. One has to do with the selection of Jacob as the child of promise rather than Esau while the other example has to do with the hardening of Pharaoh’s heart in the process of Israel’s deliverance from Egyptian bondage.
In the first example, God chose Jacob to be the one through whom the lineage of Christ should come (Rm. 9:12-13). This choice did not make it any easier for Jacob to be saved nor any more difficult for Esau. It was simply an act of mercy extended to Jacob by the hand of our sovereign God. It has nothing to do with his individual salvation.
In the second example, we observe that, in the process of delivering the Israelites from Egyptian bondage, God hardened the heart of Pharaoh (Ex. 9:12; 10:1, 20, 27; 11:10; 14:8). This allowed God to work all ten of His plagues and demonstrate to the world His superiority over the gods of Egypt. While it may puzzle us to observe that god hardened Pharaoh’s heart, we should also note that Pharaoh first hardened his own heart (Ex. 7:13, 14, 22; 8:15, 19, 32; 9:7, 34, 35). God did not make it more difficult for Pharaoh to find salvation, but allowed the stubborn will of Pharaoh to a more complete, God-glorifying deliverance.
The matter might be illustrated as follows: The sun shines on wax and on clay. It melts the wax, but hardens the clay. Pharaoh by his own free will chose to be clay. If he had chosen to be wax, God (the sun) would not have hardened him. In other words, Pharaoh would not have been hardened by the actions of God had he chosen to submit and obey His will.
So, the matters addressed in the above passage have to do with choices God has made in influencing human history rather than matters which influence individual salvation. God’s justice will not allow Him to act in such a way as to make it easier for one person to be saved and more difficult for another. All are saved on the same conditions.