Human nature in its fourfold state ... In several practical discourses

4.The sin of our nature is, of all sins, the most fixed and abiding. Sinful actions, tho' the guilt and stain of them may remain, yet in themselves they are passing. The drunkard is not always at his cup, nor the unclean person always acting lewdness. But the corruption of nature is an abiding sin: it remains with men in its full power by night and by day, at all times, fixed as with bands of iron and brass: till their nature be changed by converting grace; and the remains of it continue with the godly, until the death of the body. Pride, envy, covetousness, and the like, are not always stirring in thee. But the proud, envious, carnal nature is still with thee: even as the clock that is wrong, is not always striking wrong; but the wrong set continues with it, without great intermission.

5. It is the great reigning sin, Rom. vi. 12. Let not sin therefore reign in your mortal body, that you should obey it in the lusts thereof. There are three things you may observe in the corrupt heart. (1.) There is the corrupt nature; the corrupt set of the heart whereby men are unapt for all good, and fitted for all evil. This the apostle here calls, sin which reigns. (2.) There are particular lusts, or dispositions of that corrupt nature, which the Apostle calls the lusts thereof; such as pride, covetousness, &c (3.) There is one among these, which is (like Saul amongst the people) higher by far than the rest, namely, the sin which doth so easily beset us, Heb. xii. 1. This we usually call the predominate sin, because it doth, as it were, reign over other particular lusts; so that other lusts must yield to it. These three are like a river which divides itself into many streams, whereof one is greater than the rest. The corruption of nature is the river-head, which has many particular lusts, in which it runs: but it mainly disburdens itself into what is commonly called one's predominate sin. Now all of these being fed by the sin of our nature; it is evident that sin is the great reigning sin, which never loseth its superiority over particular lusts, that live and die with it, and by it. But as in some rivers, the main stream runs not always in one and the same channel: so particular predominants may be changed, as lusts in youth may be succeeded by covetousness in old age. Now, what doth it avail to reform in other sins, while the great reigning sin remains in its full power? What tho' some particular lust be broken? If that sin, the sin of our nature keep the throne, it will set up another in its stead: as when a water-course is stopped in one place, while the fountain is not dammed up, it will stream forth another way. And thus some cast off their prodigality, but covetousness comes up in its stead: some cast away their profanity, and the corruption of nature sends not its main stream that way as before: but it runs in another channel, namely, in that of a legal disposition, self-righteousness, or the like, so