The first problem with the above is that there are not chapter and verse numbers in Paul's original letter. The narrative of "chapter" 7 does not end with verse 7:25. It ends with 8:25, not 7:25. The exegesis in this op was built on a flawed presupposition: the chaptering determine the narrative.
It is also incorrect to say the Spirit is absent from chapter 7. The Spirit is referenced twice.
Third, the tense of the narrative goes back and forth between past, present, and future conditions and one of the most basic rules of sound exegesis is to take the text as written unless there is indication in the text itself to do otherwise. The op presuppositionally assumes there is some debate about the tense of the chapter. The proper reading is quite simple: take what is written in the past-tense as past, what is written in the present-tense and present, and what is written in the future tense as future. If anyone desires to dwell further then the Greek can be examined for perfect imperatives and other conjugations indication a past, present, and ongoing condition.
Romans 7 is NOT pre-Christian.
Paul had several problems as a person after his conversion and during his service as an apostle. Paul is frequently complaining his companions are leaving him and he doesn't handle it well. We have no reason to believe Barnabas or John Mark did anything wrong. Maybe God called them to other missions and He didn't tell Paul. On another occasion Paul indicates his own inconsistency when he writes to the Corinthians boldly about his boldness but reminds them how meek he is in person. Must have been quite aggravating to both parties. More explicitly, though, we have Paul's record of the thorn in his flesh, a messenger of satan sent to torment him. The "thorn in the flesh" is an Old Testament idiom indicating judgment. Search the OT and verify that. We also know from Job, Jesus' own temptation experience, and what he says to Peter about his being sifted, that satan goes where he's commanded and permitted to go. We also know, from the very next chapter in Romans, God works all things for good in Paul's life. By using the idiom of a thorn in his flesh he was indirectly disclosing he was under some form of judgment by God and God told Paul His grace would be sufficient.
Romans 7 is not a pre-Christian experience. It is one example of one man's experience engaging the redemptive process after having become a Christian, a process whereby the end is already decided because NOTHING can separate us from the love of God found in Christ Jesus.
The problem here is Paul already noted how the christian is made freed from enslavement to sin
Romans 6:18 (KJV)
18 Being then made free from sin, ye became the servants of righteousness.
Romans 6:22 (KJV)
22 But now being made free from sin, and become servants to God, ye have your fruit unto holiness, and the end everlasting life.
Delivered from the law to serve in newness of spirit
Romans 7:6 (KJV)
6 But now we are delivered from the law, that being dead wherein we were held; that we should serve in newness of spirit, and not
in the oldness of the letter.
How can he be a slave to sin as we see in Rom 7:14
Romans 7:14 (NET1)
14 For we know that the law is spiritual — but I am unspiritual, sold into slavery to sin.[21]
Further How is it a post conversion Paul could state
Romans 7:18 (KJV)
18 For I know that in me (that is, in my flesh,) dwelleth no good thing: for to will is present with me;
but how to perform that which is good I find not.
The answer should be obvious through the spirit as Paul states not too many verses later
Romans 8:1-10 (KJV)
1
There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
2
For the law of the Spirit of life in Christ Jesus hath made me free from the law of sin and death.
3 For what the law could not do, in that it was weak through the flesh, God sending his own Son in the likeness of sinful flesh, and for sin,
condemned sin in the flesh:
Note sins defeat
Paul adds here, In the flesh, and for this end, —
that by seeing sin conquered and abolished in our very nature, our confidence might be more certain: for it thus follows, that our nature is really become a partaker of his victory; and this is what he presently declares. Calvin's Commentaries.
this speaks of the destruction of the power of sin in a christ the very opposite of an idea tat a christians may be left enslaved by sin
4
That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.
5 For they that are after the flesh do mind the things of the flesh; but they that are after the Spirit the things of the Spirit.
6 For to be carnally minded
is death; but to be spiritually minded
is life and peace.
7 Because the carnal mind
is enmity against God: for it is not subject to the law of God, neither indeed can be.
8 So then they that are in the flesh cannot please God.
9
But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.
10 And if Christ be in you, the body is dead because of sin; but the Spirit is life because of righteousness.