Romans 7 is one of the most hotly contested scriptures in the Bible. Early Greek Fathers saw it one way, Latin Fathers saw it another. Their views come down to us today wrapped in Arminian and Calvinist interpretations and there are brilliant scholars with alternative ways of looking at it as well.

Personally, I reject Calvinism strenuously for its Manichean fatalism, introduced to Christianity by Augustine and later adopted by Calvin. However, I agree with the Calvinist camp on this particular text, with a few caveats.

With Arminians, I would agree that a regenerate person should have new motivations and be no longer DOMINATED by the sin nature. However, I disagree with the extremists who deny that there is any sin nature left to war with at all. Even Wesley, who fathered the doctrine of "Entire Sanctification", acknowledged the sin nature remains in a believer.

Only let it be remembered, that the heart, even of a believer, is not wholly purified when he is justified. Sin is then overcome, but it is not rooted out; it is conquered, but not destroyed. Experience shows him, First, that the roots of sin, self-will, pride, and idolatry, remain still in his heart. But as long as he continues to watch and pray, none of them can prevail against him. Experience teaches him, Secondly, that sin (generally pride or self-will) cleaves to his best actions: So that, even with regard to these, he finds an absolute necessity for the blood of atonement.  The Sermons of John Wesley - Sermon 123 The Deceitfulness Of The Human Heart

My view is somewhat of a " hybrid ", in the sense that I see the subject of Romans 7 to be Paul and regenerate (as Calvinists generally interpret the text), but I see free will (Arminian - libertarian) as the hinge upon which the war within swings.

There is no doubt Paul is forcefully bringing home the point that the law exposes the wretchedness of our natures, but can't cure us, showing our desperate need of salvation in Christ. Like an alcoholic who first has to admit he has a problem before he will seek a cure, Paul has to expose the wretch within, so that we see our depraved nature, our sin problem.

There is an implicit “ in and of myself ”, which undergirds Paul's statements. He is attempting to emphasize our plight - that we are helpless in OUR OWN power and a legalistic approach is utterly futile.

Romans 7 is not wholly autobiographical. Paul is drawing from personal experience, but laboring to make a point. NOT that wretched failure and depravity should be normative for a Christian, but that we have a REAL sin nature that must be overcome. Therefore, sin must be BOTH atoned for and warred against.

He uses the law to expose the sin problem, at the same time showing that legalism only exacerbates it, rather than solves it. This makes us appreciate more fully the atonement of the cross and the sanctifying influence of the Spirit. They are together brought out so beautifully in chapter 8, as the SOLUTION which brings VICTORY.

However, there is more here. WHY must the subject of chapter 7 (OF A NECESSITY) be seen as regenerate? What makes this important to the overall meaning expressed through ch. 5,6,7 and 8?

I believe it is the "NOW AND NOT YET" nature of the salvation described in the flow of these chapters, that causes some people to miss the meaning. Not maintaining the proper balance of NOW BUT NOT YET also leads some to stray too far toward Gnosticism, perfectionism, or other errors.

In Romans 7:25 Paul thanks God for salvation in Christ, yet in the very same breath reaffirms the CONFLICT REMAINS. In fact, chapter 8 describes how to fight the conflict outlined in 7 (which remains). Still, how can it remain, when Paul also said we are dead to sin and dead to the law (chapter 6)?

The answer is TIMING. We can COUNT ourselves dead to sin and alive in Christ (chapter 6) because it is a surety  IF we meet the condition of continued faith, UNTIL the redemption of our bodies (chapter 8). While inwardly groaning as we wait for the completion, chapter 7 exposes our depravity through the law, and chapter 8 shows us the cure for our depravity through life in the Spirit (and atonement).

So we are NOW dead to sin and alive "in Christ", but not FULLY dead UNTIL glorification. We ARE redeemed and no longer under condemnation, but we must CONTINUE to struggle to overcome the flesh by the Spirit. If we attempt to "freeze" any part of this transaction and remove it from the "NOW BUT NOT YET" context, we open ourselves to error.

Some say Paul (who actually thanks God for his salvation in 7:25) cannot possibly be saved (since his body in chapter  7 is subject to sin and death). These same people have absolutely no problem seeing salvation in chapter  8, YET the body is STILL subject to SIN AND DEATH in chapter 8.

Romans 8:10 But if Christ is in you, then EVEN THOUGH YOUR BODY IS SUBJECT TO DEATH BECAUSE OF SIN, the Spirit gives life because of righteousness.

So their reasoning is flawed, and an essential truth is lost. The redemption in Christ applies EVEN THOUGH our bodies are not yet glorified and STILL subject to sin and death. There is NO CONDEMNATION yet our redemption is NOT FINALIZED, until the glorification of our bodies. So there is STILL a VERY REAL struggle to face, a WAR to be fought.

1 Peter 2:11 ...abstain from fleshly lusts which wage WAR against the soul.

The old man of sin does not die easily, nor fully UNTIL we are glorified. We NEED this awareness lest we become either DISCOURAGED or COMPLACENT as we learn to walk by the Spirit and put to death the misdeeds of the body (Romans 8:13).

Encouragement for those who stumble:

1 John 2:1 I write this to you so that you will not sin. But if anybody does sin, we have an advocate with the Father--Jesus Christ, the Righteous One.

Warning Against Complacency

1 Cor 10:12 Therefore let him who thinks he stands take heed that he does not fall.

We are to strive for perfection (Phil 3:12), but practically speaking we all stumble in many ways (James 3:2) and groan inwardly until the final glorification of our bodies (Romans 8:23). There is no excuse for sin, for the power to OVERCOME is available and we are required to do so. Not that we will never sin, but it shall not be our master , we will not habitually  sin, we will not make a  practice  of sin.

The Spirit can be resisted, grieved, even quenched, so if we do sin it's because of our free will choice, not because the power to overcome is not available. Thus " predestined monergism " and " once saved always saved " are falsified by how we relate to the " already, but not yet " nature of the salvation process. We must cooperate with the Spirit, and it's not over until we are glorified. The process is synergistic and ongoing. If you choose to give up along the way, you will make a "shipwreck of your faith" (1 Tim 1:9). 

Hebrews 3:14  For we have become partakers of Christ  IF we hold fast the beginning of our assurance firm until the end...

Rev. 21:7 He who overcomes will inherit these things, and I will be his God and he will be My son.

Those who deny the struggle of the regenerate taught in Romans 7 and 8 are on a dangerous path. When practical experience doesn't live up to their theology, disillusionment or self-deception are inevitable. We must overcome, but it is not easy or instantaneous.

Perseverance is required, real commitment over a lifetime. We will have difficult battles to fight but the Spirit will help us if we let him. If we have a temporary setback, forgiveness is available. We must not become discouraged - we must keep moving forward - we must overcome.

Romans 8:13  For if you live according to the flesh, you will die; but IF by the Spirit you put to death the misdeeds of the body, you will live.

"Proclamation of a gospel which promises only pardon, peace and power will result in converts who sooner or later become disillusioned or deceitful about their Christian experience.” (Dunn, Romans 7: 14-25 in the Theology of Paul, pg. 273).

For more on salvation please read this article on soteriology called -  Grace - Sovereign, Free, or Saving .