The corrupt will is the real cause of unbelief

“No man can come to me, except the Father which hath sent me draw him: and I will raise him up at the last day. - John 6:44

Until the Father draws the heart of man by His grace, man will not believe.

The solemn truth contained in these words is one that needs careful weighing. It is vain to deny that without the grace of God no one ever can become a true Christian. We are spiritually dead, and have no power to give ourselves life. We need a new principle put in us from above. Facts prove it. Preachers see it. The Tenth Article of our own Church expressly declares it—"The condition of man after the fall of Adam is such that he cannot turn and prepare himself, by his own natural strength and good works, to faith and calling upon God." This witness is true.

But after all, of what does this inability of man consist? In what part of our inward nature does this impotence reside? Here is a point on which many mistakes arise. Forever let us remember that the will of man is the part of him which is in fault. His inability is not physical, but moral. It would not be true to say that a man has a real wish and desire to come to Christ, but no power to come. It would be far more true to say that a man has no power to come because he has no desire or wish. It is not true that he would come if he could. It is true that he could come if he would. The corrupt will—the secret disinclination—the lack of heart, are the real causes of unbelief. It is here the mischief lies. The power that we lack is a new will. It is precisely at this point that we need the "drawing" of the Father.

– J. C. Ryle, Commentary on Gospel of John