In chapter five of Indwelling Sin in Believers, John Owen described how “Aversion to Holiness” was part of our continuing enmity against God. He said where there is mutual enmity there is mutual “aversation,” an older term for intense aversion. He described its meaning as a turning from God and all things associated with Him in disgust. Then in chapter six he begins to unpack how enmity against God was seen in opposition to God and his law. “Where there is enmity, there will be fighting; it is the proper and natural product of it.”

The force of indwelling sin is first seen in its general inclination to lust after things opposed to God and his law (Galatians 5:17). These cravings are not just physical as with drunkenness. They also exist in the mind (Ephesians 2:3)—“the faculties and affections of the soul.” When an individual is in this lustful state of mind, every intention of their heart is set continuously on evil (Genesis 6:5).

It is in the heart like poison that hath nothing to allay its venomous qualities, and so infects whatever it touches. And where the power and dominion of it is broken, yet in its own nature it hath still an habitual propensity unto that which is evil, wherein its lusting doth consist.

Owen likened indwelling sin to a river. While its springs and fountains are open, its water flows continually. If you merely try to restrict it with a dam, it will rise and swell until it overflows its banks. But if you dry up the springs that feed the river, what remains may be restrained. However, as long as there is any running water, “It will constantly press upon what stands before it.”

So is it with indwelling sin; whilst the springs and fountains of it are open, in vain is it for men to set a dam before it by their convictions, resolutions, vows, and promises. They may check it for a while, but it will increase, rise high, and rage, at one time or another, until it bears down all those convictions and resolutions, or makes itself an under-ground passage by some secret lust, that shall give a full vent unto it. But now, suppose that the springs of it are much dried up by regenerating grace, the streams or actings of it abated by holiness, yet whilst any thing remains of it, it will be pressing constantly to have vent, to press forward into actual sin; and this is its lusting.

This habitual inclination manifests itself by its readiness “to join and close with every temptation whereby it may possibly be excited.” Just as fire will burn whatever is combustible, temptation will consume anything that may possibly excite it. And not only does the person have to address the outward temptation of sin, but also where it dwells within their own heart. So what is temptation?

It is raising up in the heart, and proposing unto the mind and affections, that which is evil; trying, as it were, whether the soul will close with its suggestions, or how far it will carry them on, though it do not wholly prevail. Now, when such a temptation comes from without, it is unto the soul an indifferent thing, neither good nor evil, unless it be consented unto; but the very proposal from within, it being the soul’s own act, is its sin. And this is the work of the law of sin,—it is restlessly and continually raising up and proposing innumerable various forms and appearances of evil, in this or that kind, indeed in every kind that the nature of man is capable to exercise corruption in. Something or other, in matter, or manner, or circumstance, inordinate, unspiritual, unanswerable unto the rule, it hatcheth and proposeth unto the soul.

Not only does indwelling sin stir up lusts by proposing “inordinate figments” to the will, it also seeks to assault the soul and rule over it. Referring to Romans 7:23, Owen said there seems to be two laws within us—the law of sin and the law of grace. “But contrary laws cannot both obtain sovereign power over the same person, at the same time.” So they war against each other. The law of sin will oppose the general purpose and course of the law of grace within the believer and it will oppose particular duties.

The general purpose and course of the believer’s heart is to walk in universal conformity to the Spirit of Christ in all things. Yet we also see where we falter in the pursuit of this purpose. The frame of the heart is changed. Its affections are entangled; there are eruptions of unbelief and distempered passions. Carnal wisdom and all its manifestations are set to work. “And all this is from the rebellion of this law of sin, stirring up and provoking the heart unto disobedience.”

We cannot walk according to the law of grace “because of the contrariety and rebellion of this law of sin.” It opposes everything commanded by or approved by the law of grace. Not only does indwelling sin oppose the law of grace; it also assaults to soul. It attempts to rule over us. And this warfare consists of the following things.

• It attacks the soul by stirring up sin by “the vanity of the mind,” or “the sensuality of the affections” or the folly of the imaginations.”
• It attacks the soul “when the law of grace is not actually putting it on duty.” It will relentlessly attack again and again.

Rebuke them by the power of grace; they withdraw for a while, and return again. Set before them the cross of Christ; they do as those that came to take him,—at sight of him they went backwards and fell unto the ground, but they arose again and laid hands on him,—sin gives place for a season, but returns and presseth on the soul again.

• It also attacks by entangling the affections and drawing them into a struggle against the mind.

If the law of sin gets a hold upon one or more affections, “it hath gotten a fort from whence it continually assaults the soul.” So the primary duty of mortification of the flesh is directed at the affections: “Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry” (Colossians 3:5). If the law of sin can possess any affection, it will make it the base of its assault against the soul.

Now, then, when this law of sin can possess any affection, whatever it be, love, delight, fear, it will make from it and by it fearful assaults upon the soul. For instance, hath it got the love of any one entangled with the world or the things of it, the lust of the flesh, the lust of the eyes, or the pride of life?—how will it take advantage on every occasion to break in upon the soul! It shall do nothing, attempt nothing, be in no place or company, perform no duty, private or public, but sin will have one blow or other at it; it will be one way or other soliciting for itself.

Owen said this was the sum of how the law of sin fought and warred against our souls. Reflecting on these things is advantageous to believers, as they will teach us “to walk humbly and mournfully before God.”