Romans 8:12–13—The flesh further defined, a startling warning, and the Spirit.

Paul repeats the core of his teaching on Christians’ responsibility in regard to sin (6:11–18), but he adds a stronger warning and an essential new ingredient. Paul did not mention in chapter 6 the Holy Spirit. Here in the chapter that celebrates the Spirit’s ministry, Paul tells believers to rely on the power of the Spirit for victory over sin. Not doing so risks death.

Flesh as a power seeking our destruction
Still speaking to believers, Paul refers three times in these verses to “the flesh,” a by now familiar term that appears three times in these verses. I have discussed Paul’s term “flesh” (sarx) several times already in this chapter and the one preceding it, noting that its meaning varies with context. Generally, though, Paul uses it to represent worldly life hostile to God and that is its meaning here.

In these two verses, Paul makes three additional points: (1) we owe no obligation to the flesh, (2) but we can live according to it, (3) so we must rely on the Holy Spirit. Because the consequence of not doing so is severe—“you will die,” meaning eternal death—we had better understand our relationship with the flesh.

Flesh does not mean sinful nature as if God adds to Christians a good nature on top of our original bad nature and the two compete for our attention. As I explain in my book, sanctification does not involve a contest between two natures, but rather “a life lived in alignment with the Christian’s true identity—a born-again child of God with a new heart from which springs the desire to obey God.” (After the NIV in 2011 stopped translating flesh as sinful nature, only one modern translation, the New Living Translation, still does so.)

As Douglas Moo explains, “flesh and Spirit stand over against each other not as parts of a person (an anthropological dualism), nor even as impulses or powers within a person, but as the powers, or dominating features, of the two ‘realms’ of salvation history.” It helps to realize that we Christians live in the new realm but meet resistance from the old. Christ has brought us into the new age of the Spirit, but we must still contend with the flesh, a powerful remnant of the old age. In like fashion, we are no longer of this world, though it entices us to return through the desires of the flesh (see 1 John 2:15–16). Flash fosters love for the world.

The following metaphor conveys my understanding of flesh, and I hope it clarifies for you both the meaning of the concept as Paul uses it here and its close relationship to the dominion of sin.

Life in the fog (under the dominion of sin)
All humanity, Jews and Gentiles alike, unless they are saved through Christ, live under a fog of spiritual darkness. That fog is the dominion of sin and death, and it is the realm occupied by everyone born in the likeness of Adam, who forfeited his dominion to the rule of Satan and the power of sin. Life under the dominion of sin is characterized by two things: indifference or outright hostility to God and worldly mindsets and lifestyles. And this brings us to the meaning of flesh.

Flesh is a worldly way of life that fools people into thinking the fog is not only the best place to live but also the only place to live. Flesh very much enjoys being in the fog. It is what attracts people to remain under the dominion of sin, some of them enthusiastically, many others sadly, everyone unknowingly.

Flesh predisposes people to think and act ungodly—not only to indulge bodily appetites but also to seek power over others, take what is not ours, and rejoice at others’ failure. One of its key characteristics is life as I choose, with me in charge, for my own benefit. But even when people try in their own strength apart from God to be selfless, generous, and kind they are still in the realm of the flesh. The Message Bible appropriately calls the flesh “this old do-it-yourself life.”

Fog gone but flesh remains
When a person gives up that old life and turns to Jesus Christ, the fog immediately lifts. We saw in chapter 6 how Jesus freed us from the fog (dominion of sin). In his experience as a man on the earth, Jesus subjected himself to the fog and conquered it through his death (see 6:10 and 6:14).

Jesus said, “I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life” (John 8:12). Those of us who have made that decision now see. We walk under an open heaven, able to see God, ourselves, and his creation in a new light. As David said, “In your light we see light” (Ps 36:9).

As for our identity, our status, how God sees us, we are not “in the flesh” (verse 9), no longer in the realm of its control over us. But the flesh remains a force we have to deal with, as it tempts us to partake once again of its worldly mindsets, values, and pleasures. Just as walking in the light is an ongoing challenge for believers (see 1 John 1:7), so is the choice Paul sets before us in these verses. We must and by the Spirit we can resist the flesh, which we could not do before our regeneration as people of the Spirit.

Because a chapter of my book describes our responsibility to resist sin and walk by the Spirit, I need not repeat any of that content here. Left for us to consider is what Paul means by his warning in verse 13.

A matter of death or life
Paul speaks to Christians, addressing the Roman believers and us as “brothers.” How shocking it is, therefore, to see that we will die—and he has to mean eternal death—if we live according to the flesh. It’s a warning we cannot ignore or explain away by our theological presuppositions. Moo cites some of the assurances Paul has given to believers (5:9–10, 21; 8:1–4, 10–11) and notes that we cannot synthesize them with this warning in a neat logical arrangement.

Moo concludes, “Paul insists that what God has done for us in Christ is the sole and final grounds for our eternal life at the same time as he insists on the indispensability of holy living as the precondition for attaining that life.” Also indispensable is the Holy Spirit, and Paul’s warning certainly reinforces the necessity of our dependence on the Spirit for godly living.

Eternal life is the outcome for us when by the Spirit we put to death (mortify) the deeds (practices) of the body (soma). “Body” is not equivalent to flesh, but Paul evidently uses it here as a potential instrument of the flesh. Moo sees Paul as meaning “deeds worked out through the body under the influence of the flesh.”

Paul’s use of present tense (“if you live according to the flesh”) signifies an ongoing lifestyle of fleshly values and behaviors as I described above. A (supposed) believer who lives in this manner has turned away from Christ to go back to the world, back under the foggy dominion of sin and death. The penalty for doing that: “you will die.”