"But so Augustine then argued that the core engine of human nature is not our will, but our heart and its desires. He pointed out that it's really, really hard, however, unfortunately, to change hearts. So hard, in fact, that only God can do it through the Holy Spirit.

The way you change a person is by getting through not to their head, or to their will, but to their heart. And this is the work of the Holy Spirit, the things of God and to make us hate and flee from bad and self-destructive desires."