Fight Your Sin

Know that victory over sin has already been won.

Before we address fighting sin, it is worthwhile to point out that the victory over sin has already been won in Christ. The good news of the gospel is that Jesus has defeated sin, death, and evil through his own death and resurrection and is making all things new, even us. Paul explains Jesus’s victory over sin and its implications for us in Romans 6:6-11:

  • The power of sin has been rendered powerless, as we are no longer enslaved to it but to Christ!
  • However, disciples will continue to battle sin until our final reunion with Christ. This is why Paul exhorts us to “consider” ourselves dead to sin and alive in Jesus.
  • The time between the cross and the return of Christ will be filled with battles against sin, but in these battles we possess a new life which enables us to defeat sin through Christ’s decisive victory.
  • The fight of faith is a fight to be our new, authentic selves in Christ, free from sin and alive to God in righteousness. Knowing our sin, we fight against it by fighting to be who we already are in Christ.

Why Fight?

Fighting your sin is a tenacity to put sin to death, which arises from our life in Christ. Unfortunately, many disciples do not walk in their newness of life but in old patterns of sin. Perhaps this lackadaisical approach to sin is because we value Jesus’s atonement for our guilt and the penalty of sin, but at a heart level fail to value and understand how his atonement has also freed us from the power of sin? Or perhaps our indifference to fighting sin springs from a false belief that God accepts us just as we are, not as who we will be? Why fight if we are already accepted?

However, if we are accepted not as we are but as we are in Christ, we have every reason to fight—from our new identity. The truth is, persistent, unrepentant sin can disqualify us from the kingdom of God (Gal. 5:19–21; Eph. 5:5; Heb. 3:7–13). God does not accept us as we are. He accepts us as we are in Christ. In him, we are new creation (2 Cor. 5:16; Gal. 6:15), and new creatures live transformed (not perfect) lives. As recipients of God’s grace, we are compelled to follow Jesus in all of life. We will fight to find Jesus sweeter, richer, deeper, and more satisfying than anything else in the world. Disciples contend with their sin because they love their Savior.

As recipients of God’s grace, we are compelled to follow Jesus in all of life.

The Mortification of Sin

In my discipleship, the writings of John Owen continue to be tremendously helpful. Owen’s books, Of the Mortification of Sin and On Temptation, are classics on the subject of fighting sin. Owen articulates the purpose for his writing on the subject: “That mortification and universal holiness may be promoted in my own and in the hearts and ways of others, to the glory of God; so that the gospel of our Lord and Saviour Jesus Christ may be adorned in all things.” Mortification is that tenacious disposition of the heart that longs to defeat sin out of love for Jesus. Notice that Owen sets mortification of sin in its rightful place, not as an end in itself, but as a means to making much of the gospel of Christ. Owen keeps the gospel, not fighting, central to discipleship, while retaining an appropriate tenacity in fighting our relentless foe. He writes: “Be killing sin lest it be killing you.” Paul issues similar injunctions:

  • "Put to death therefore what is earthly in you: sexual immorality, impurity, passion, evil desire, and covetousness, which is idolatry. On account of these the wrath of God is coming.” (Col. 3:5–6)
  • “For if you live according to the flesh you will die, but if by the Spirit you put to death the deeds of the body, you will live.” (Rom. 8:13)
  • “Take care, brothers, lest there be in any of you an evil, unbelieving heart, leading you to fall away from the living God. But exhort one another every day, as long as it is called ‘today,’ that none of you may be hardened by the deceitfulness of sin.” (Heb. 3:12–13)

Sin is no light-hearted matter. It is crouching at our door and we must master it (Gen. 4:7). It is dangerous to not fight sin. It is a sobering fight that must not cease. Fight your sin means a habitual weakening of the flesh through constant fighting and contending in the Spirit for sweet victory over sin. It should be regular and progressive, not occasional and instant. Fighting is not an end in itself or a way to make us more presentable to God. We fight because we have been made presentable in Christ and want to escape deceit of any kind. We fight for belief in his gospel the truest and best news on earth—that Jesus has defeated our sin, death, and evil, through his own death and resurrection, and is making all things new, even us. Until all things are new, we will continue to fight the good fight of faith.

Fighting is ultimately about life, not death—about joy, not sorrow. It is about the gospel, not good works. We don’t fight for acceptance; we fight from our acceptance. We don’t contend against sin to forge an identity but because we have received a new identity in Christ. Perfection is not the goal; persevering faith is.

Yesterday we posted the first of three in a series on fighting sin. Check out the post on the importance of knowing your sin. Once we know our sin, the challenge is to actually fight it.

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