19 For the good that I would I do not: but the evil which I would not, that I do. 20 Now if I do that I would not, it is no more I that do it, but sin that dwelleth in me. (Romans 7:19-20 KJV)
William Burkitt’s Commentary
Here Apostle Paul repeats what he had before asserted; namely, That he did not always do the good that he desired to do, but sometimes being overpowered by the flesh, did what the law prohibits, and what he would not do.
And further adds, That it was no longer himself, (chusing and approving the action in his mind) that did this, but sin dwelling in him, which sometimes hurried him to the commission of it, against the inclination and law of his mind.
Here note, 1. That the corruption of nature in the soul of man is a real, but distinct thing from the soul itself. A dweller in a house is really distinguished from the house he dwells in. Sin is not a substance, but the pravity, and depravity of our faculties.
Note, 2. That the corruption of our own hearts and natures is the root and cause of all that evil that is done by us.
Note, 3. That the habitual bent, the settled purpose, and determinate resolution of a Christian’s will, is against all sin; and he does not sin with the full consent of his will. Although there are not two distinct persons, yet there are two distinct principles in a regenerate man.
Sin and he are distinguished. In a good man, there is a conflict between sin and grace, but in an unregenerate man there is no combat between the flesh and the Spirit; for he is all flesh; the flesh and he are one; the combat is not between grace and sin, but between one sin and another, and between one faculty and another: Light in the understanding opposes lust in the will; whereas the conflict in a gracious person is not between his judgment and his will, but between the regenerate and unregenerate part in his will.
Sin, like a preternatural bias, clapped upon the soul, sometimes carries it away from the mark which the Christian aims at: However, though a good man be overcome in praelio, yet not in bello; though grace is sometimes foiled in the combat, yet it keeps the field, maintains and recovers its ground. The saint will not throw down the weapon till he lays down his life, and grace shall at length be finally victorious.