Matthew Henry Commentary Romans 7:18-22

"For I know that in me, that is, in my flesh, dwelleth no good thing: for to will is present with me, but to do that which is good [is] not. For the good which I would I do not: but the evil which I would not, that I practise. But if what I would not, that I do, it is no more I that do it, but sin which dwelleth in me. I find then the law, that, to me who would do good, evil is present. For I delight in the law of God after the inward man:" — Romans 7:18-22 (ASV)

The purer and holier the heart is, the more keenly it will perceive the sin that remains in it. The believer sees more of the beauty of holiness and the excellence of the law. Their earnest desires to obey increase as they grow in grace. However, the complete good toward which their will is fully set, they do not do; with sin continually springing up in them through remaining corruption, they often do evil, though this is against the firm determination of their will.

The stirrings of sin within grieved the apostle. If the striving of the flesh against the Spirit meant that he could not do or perform what the Spirit suggested, then likewise, through the effective opposition of the Spirit, he could not do what the flesh prompted him to do. How different this situation is from that of those who are complacent about the inward stirrings of the flesh prompting them to evil—who, against the light and warning of conscience, continue, even in outward practice, to do evil and thus, deliberately, continue on the road to perdition!

For since the believer is under grace, and their will is set on the way of holiness, they sincerely delight in the law of God, and in the holiness which it demands, according to their inward man; that new man in them, which after God is created in true holiness.