Romans 7 and the majority of 8 (ESV), below, is supposed to explicate Paul's attitude to Sin and the Law (i.e. Torah commandments). I have colour-coded it to show in red what I estimate as interpolation:
The triple expostulation in 7:7 is transparently an attempt to row back the authentic Paul's principle that the Law was captivity and an evil instrument, for it both "aroused" the sinful passions of the flesh and applied the punishment for Sin. This rowing back is bookended on the other end of the passage with the pseudo-inference, "So the law is holy", which bears no logical relation to the foregoing argument. How can Paul honestly be supposed to have argued that the Law arouses Sin, made it come alive, killed him, and therefore is holy? This is a transparent attempt to assert by interpolation that Paul meant the opposite of what he was trying to communicate.7 Or do you not know, brothers—for I am speaking to those who know the law—that the law is binding on a person only as long as he lives? 2 For a married woman is bound by law to her husband while he lives, but if her husband dies she is released from the law of marriage. 3 Accordingly, she will be called an adulteress if she lives with another man while her husband is alive. But if her husband dies, she is free from that law, and if she marries another man she is not an adulteress.4 Likewise, my brothers, you also have died to the law through the body of Christ, so that you may belong to another, to him who has been raised from the dead, in order that we may bear fruit for God. 5 For while we were living in the flesh, our sinful passions, aroused by the law, were at work in our members to bear fruit for death. 6 But now we are released from the law, having died to that which held us captive, so that we serve in the new way of the Spirit and not in the old way of the written code.
7 What then shall we say? That the law is sin? By no means! Yet if it had not been for the law, I would not have known sin. For I would not have known what it is to covet if the law had not said, “You shall not covet.” 8 But sin, seizing an opportunity through the commandment, produced in me all kinds of covetousness. For apart from the law, sin lies dead. 9 I was once alive apart from the law, but when the commandment came, sin came alive and I died. 10 The very commandment that promised life proved to be death to me. 11 For sin, seizing an opportunity through the commandment, deceived me and through it killed me. 12 So the law is holy, and the commandment is holy and righteous and good.
The chapter as it continues is interpolation:
13 Did that which is good, then, bring death to me? By no means! It was sin, producing death in me through what is good, in order that sin might be shown to be sin, and through the commandment might become sinful beyond measure. 14 For we know that the law is spiritual, but I am of the flesh, sold under sin. 15 For I do not understand my own actions. For I do not do what I want, but I do the very thing I hate. 16 Now if I do what I do not want, I agree with the law, that it is good. 17 So now it is no longer I who do it, but sin that dwells within me. 18 For I know that nothing good dwells in me, that is, in my flesh. For I have the desire to do what is right, but not the ability to carry it out. 19 For I do not do the good I want, but the evil I do not want is what I keep on doing. 20 Now if I do what I do not want, it is no longer I who do it, but sin that dwells within me.The curiosity is that only now do we read an argument for how the Law can both be holy and arouse Sin: the argument comes after the conclusion falsely tacked on to the authentic Paul's contrary argument above! The solution the interpolator has come to, is to argue that while the Law is holy, Sin is inherent in the flesh, a traitor to oneself embodied in the physical nature of humanity.
21 So I find it to be a law that when I want to do right, evil lies close at hand. 22 For I delight in the law of God, in my inner being, 23 but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members. 24 Wretched man that I am! Who will deliver me from this body of death? 25 Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin.Who can take seriously the idea of a Paul who says, "I delight in the law of God ... I myself serve the law of God with my mind", when this is supposed to be the same Paul who said in the epistle to the Galatians: "I testify again to every man who accepts circumcision that he is obligated to keep the whole law. You are severed from Christ, you who would be justified by the law; you have fallen away from grace" and "all who rely on works of the law are under a curse"? Does Paul "delight" in the Law from which he has already been "released" (Romans 7:6), the Law that "aroused" Sin, the Law apart from which Sin lies ded, the Law to conform to which is to be severed from Christ and laid under a curse?
8 There is therefore now no condemnation for those who are in Christ Jesus. 2 For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. 3 For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, 4 in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit. 5 For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. 6 For to set the mind on the flesh is death, but to set the mind on the Spirit is life and peace. 7 For the mind that is set on the flesh is hostile to God, for it does not submit to God's law; indeed, it cannot. 8 Those who are in the flesh cannot please God.The pseudo-Pauline soteriology here is a separate theory from that already stated in Romans 7:1-6. The interpolator's soteriology is that Jesus' death substituted for our punishment for our sins; the authentic Pauline soteriology of 7:1-6 is that the Christian faithful have already "died to the Law". This authentic soteriology is explicated by the point made about baptism and death in Romans 6: "Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, in order that, just as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life." Paul's authentic soteriology is that since the baptised have died once by union with the resurrected Christ, they cannot be punished with death under the Law, for one can die but once: "We know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. For the death he died he died to sin, once for all, but the life he lives he lives to God. So you also must consider yourselves dead to sin and alive to God in Christ Jesus."
9 You, however, are not in the flesh but in the Spirit, if in fact the Spirit of God dwells in you. Anyone who does not have the Spirit of Christ does not belong to him. 10 But if Christ is in you, although the body is dead because of sin, the Spirit is life because of righteousness. 11 If the Spirit of him who raised Jesus from the dead dwells in you, he who raised Christ Jesus from the dead will also give life to your mortal bodies through his Spirit who dwells in you. 12 So then, brothers, we are debtors, not to the flesh, to live according to the flesh. 13 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.The authentic Paul would not have said, "the body is dead because of sin", because he had already said why the body is dead and resurrected: baptism into Christ's death and resurrection.
14 For all who are led by the Spirit of God are sons of God. 15 For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, “Abba! Father!” 16 The Spirit himself bears witness with our spirit that we are children of God, 17 and if children, then heirs—heirs of God and fellow heirs with Christ, provided we suffer with him in order that we may also be glorified with him.Here we seem to be back with the authentic Paul, as identified by the idea of the "spirit of slavery", which by comparison with Galatians would seem to imply attachment to captivity under the Law, as promoted by Jews and the Jerusalem apostles.
The most natural way to interpret Paul is in this and similar ways, to notice the contrary arguments and nonsensical bookendings, and to pay attention to the way his epistles are incoherent. The viewpoint the interpolators are trying to row back, is most likely the authentic one.