Realize that Paul is writing this to church members in Rome sometime in the mid-AD 50s, and this war between his desire to do good and the evil that he finds himself practicing is still taking place within him. How long had he been a converted son of God by this time? Historians place the calling of the apostle on the road to Damascus in the early mid-30s, perhaps as early as AD 33-34. Thus, by this time, he had likely been converted for about twenty years—and he was still intensely and uncomfortably aware of the struggle against the "law of sin" occurring in him. This battle was being fought internally, he says in verse 18, in his flesh, and in verse 23, in his members.

He is telling us, "I don't want to do evil! It is my will not to do it, but too often I find myself caving in to it." In his mind, he knew he should not do these things, but he would do it anyway because of the evil that remained in his flesh. Even after a long period of conversion, there is an evil "law," as Paul calls it—we could also call it a principle, an attitude, a mindset, a tendency, an inclination—still present within us. It is almost like our worse nature (as opposed to our "better nature")—a kind of "devil on your shoulder." Worse still, it is in us!

Earlier, in Romans 7:14, Paul had given another insight into this evil in us: "For we know that [God's] law is spiritual, but I am carnal, sold under sin." He is again speaking of this tendency toward evil because of the flesh that clothes us, which he names "carnality." Our carnality is what sells us into slavery to sin. A significant and necessary responsibility that falls to us upon our redemption through the liberating blood of Jesus Christ is to cease being slaves of sin and, instead, become slaves of righteousness (see Romans 6:15-23).

However, it is a terrible struggle—an all-out war—because, with our minds, we have already thrown off the shackles of sin, but our bodies, still receiving orders from the human nature that remains with us, are always trying to return us to those shackles. The battle goes back and forth—sometimes, our spiritual mind triumphs, and other times, we let our flesh prevail. Unfortunately, this conflict will rage until we die, but we can thank God that He covers these frequent—yet, we hope, diminishing—lapses.