Quoting Charles H. Spurgeon:
We declare on scriptural authority that the human will is so desperately set on mischief, so depraved, so inclined to everything that is evil, and so disinclined to everything that is good, that without the powerful, supernatural, irresistible influence of the Holy Spirit, no one will ever be constrained toward Christ.
A man is not saved against his will, but he is made willing by the operation of the Holy Spirit. A mighty grace which he does not wish to resist enters into the man, disarms him, makes a new creature of him, and he is saved.
If I did not believe that there was might going forth with the word of Jesus which makes men willing, and which turns them from the error of their ways by the mighty, overwhelming, constraining force of divine influence, I should cease to glory in the cross of Christ.