Featured Do Christians still have their old nature/flesh after salvation?

I believe you are correct. I will take a stab at it.


Rom 7:14 For we know that the law is spiritual: but I am carnal, sold under sin.
Paul is giving his own testimony as a believer. He continues to use the first person singular. The entire passage from 7:1-8:4 is a detailed explanation how the law relates to our (Christian) faith. In 7:7-13 he had been talking about the law and sin, and now from verse 14 he begins with “the believer and sin.” Paul uses himself as an example.
“The law is spiritual.” Hence, I (Paul) am unspiritual. He adds that he is “sold under sin.” This also correlates with what he has written in Rom.3:9 (“we…both Jews and Gentiles…are all under sin.”) From verse 14 onward Paul uses the present tense whereas before this he had not. This is his present life, his personal Christian testimony. He is describing the conflict that rages within every believer. The phrase “sold under sin” may describe the unregenerate, but it describes the sin in the believer. Every one of us are subject to the penalty of sin which is death. We are subject to consequence of sin—separation from God in a spiritual way. Sin separates from God, that is, our fellowship is broken until sin is repented of. 1John 1:9 is for the believer. We must confess our sin in order to restore our fellowship. Indwelling sin is there and seeks to claim its hold over the believer.

Rom 7:15 For that which I do I allow not: for what I would, that do I not; but what I hate, that do I.
Rom 7:16 If then I do that which I would not, I consent unto the law that it is good.
Rom 7:17 Now then it is no more I that do it, but sin that dwelleth in me.
Paul is putting his actions in the simplest language possible that we might understand him.
In the WEB
Romans 7:15 For I don't know what I am doing. For I don't practice what I desire to do; but what I hate, that I do.
He doesn’t understand it himself. What is going on? I am not doing the things that I want to do.
Then conversely he says: The things that I hate are things that I am doing.
Paul is speaking of his own struggle. The passage is about the law and its relation to sin, specifically now Paul’s sin and his struggle with it. There are two natures and they are battling each other. Remember that Paul is using himself as an example of this battle.
In the unregenerate the battle is inferred in Romans 2:14,15, but Paul is describing himself. He has already described the law as being holy and good; an unsaved person would never admit to that.
Therefore Paul concludes, it is no more I that do it, but sin that dwells in me (vs. 17). Paul is not avoiding personal responsibility but rather speaking of his desire to do good and the power of sin dwelling within him. It is a battle, a battle that rages within every believer.

Rom 7:18 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.
Rom 7:19 For the good that I would I do not: but the evil which I would not, that I do.
Rom 7:20 Now if I do that I would not, it is no more I that do it, but sin that dwelleth in me.
Keep in mind that the Law is always good. Everything here is contrasted to the Law. That is the context. Compared to the Law there is nothing good in Paul. Breaking the law is sin. All of us break the law—every day. When Paul says: “I know that in me,” he defines “in me.” “That is in my flesh” or in my sin nature. The phrase refers to the sin nature that dwells within Paul as it dwells within all of us. We can’t escape it and won’t escape it until we reach heaven. He is not referring to material flesh, but rather the principle of sin that dwells within him.
He continues: “I desire to do good, but I can’t do it” (18b). He has stated this in verse 15 and says it again in verse 20. As a believer there is sin that dwells within him. That sin once owned him as an unbeliever, but even now it still dwells in him. He is not free from it. There are things he does not want to do but does them anyway. It is a problem we all have.

Rom 7:21 I find then a law, that, when I would do good, evil is present with me.
Rom 7:22 For I delight in the law of God after the inward man:
Rom 7:23 But I see another law in my members, warring against the law of my mind, and bringing me into captivity to the law of sin which is in my members.
Paul is not coming to his conclusion. The law he refers to is not the Law, but a principle that he has drawn from his own experience. “Whenever I do good, evil is present with me.”
We all know that to be true. The more we battle for Christ, the greater Satan battles against us.
Evil is always present whenever we try to do good. It is a simple fact of life. That is what is stated in verse 21. No one can argue against that.
Verse 22 is a direct reference both to Psalm one and to Psalm 119, where the Psalmist repeatedly says that he delights in the law of God.
In verse 23 Paul recognizes the sin principle that he has already referred to. This is the law of sin and it wars against the law of his mind which delights in the law of God. Previously he had called it “sin living in me” (vs. 7, 20). It is waging war against his new nature, which is the mind of the believer. It is making him a prisoner of the law of sin. This indwelling principle of sin is constantly warring against us, battling against our new nature, causing conflict within us, and trying to gain victory and control.
The new nature is referred to as the “law of the mind” because it has the capacity of making moral judgments. Paul comes to the conclusion in verses 24 and 25:

Rom 7:24 O wretched man that I am! who shall deliver me from the body of this death?
Rom 7:25 I thank God through Jesus Christ our Lord. So then with the mind I myself serve the law of God; but with the flesh the law of sin.
In desperation he cries out” O wretched man that I am. It is his picture of himself.
“Who shall rescue me from the body of this death?” In himself he can do nothing. An unregenerate person faces an impossible situation. There is no solution. But there is a solution with Christ. His answer is immediate and triumphant.
“Thanks be unto God through Jesus Christ our Lord.”
Notice that no unsaved person could pen these words. This is Paul’s testimony. He identifies himself immediately with the Lord Jesus Christ.
“With the mind I serve the law of God.” The word “serve” meaning as a slave I am serving the law of God, but in my sinful flesh. We wait for the redemption of our bodies.
But if I give into this principle of sin, my sinful nature, I will serve the law of sin. There is a choice. The battle is in the mind.
As Joshua said to the Israelites: “Choose ye this day whom ye will serve.” (Josh.24:15)

 

Really, the only verse one must deal with is Romans 7:14. If this text refers to the unglorified condition of the child of God, then, the argument is over.

14 ¶ For we know that the law is spiritual: but I am carnal, sold under sin.

Paul has just stated that law is just, holy and good, but that is not entirely true of the present condition of the child of God. Indeed, Paul spells out an internal conflict within his own person in verses 15-16:

15 For that which I do I allow not: for what I would, that do I not; but what I hate, that do I.
16 If then I do that which I would not, I consent unto the law that it is good.

Once, he has clearly declared this internal conflict in his Person, in verses 17-18 he carefully identifies what aspect is responsible for "what I hate,that I do" while equally declaring that another aspect of himself is clearly not to be blamed for this proneness to do evil:

17 Now then it is no more I that do it, but sin that dwelleth in me.
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.


He denies that "I that do it, but sin that dwelleth IN ME in verse 17. In verse 18 he explicitly identifies that part in his nature from which this proneness for evil originates. "For I know that IN ME (THAT IS IN MY FLESH) dwelleth no good thing.

The problem is not with his will "for to will is present with me" to do good, the problem is lack of power "but how to perform that which is good I find not." - Meaning he cannot find it "IN ME."

He can find the will to do good "IN ME". He can find "IN ME" the inward man which DELIGHTS in the law of God, but he cannot find "IN ME" power to overule what he identifes "IN ME" the law of sin operating "in my flesh."

It is this "flesh" that is not redeemed, and never will be redeemed in this life, but will actually either suffer "death" and that is why he calls it "this body OF DEATH.' that he seeks deliverance from.

Indeed, he liken's that aspect of himself where the law of sin operates in "this body" "the flesh" as to a corpse which Roman Soliders would chain to a misbehaving prisoner. They would chain the dead body face to face, arm to arm, waist to waist, leg to leg, until that prisoner actually died. Only physical death or incorruption being put on and corruption being removed would resolve this problem for the child of God. Hence, "this body" "the flesh" is that aspect of the child of God which "is sold under sin" and it will suffer the condemnation of sin - death or be destroyed in glorification.

 

Agreed, depending on the ambiguity of the terms "nature" and "unglorified condition"


Paul is simply speaking of a dichotomy:

1) the sinless inner man, which has been washed in regeneration (Titus 3:5), perfected by the blood of Christ (Hebrews 10:4, 14), is a new creation (2Corinthians 5:17), and cannot sin (1John 3:9)

2) the sin-wrecked outer man, this body of death (Romans 7:25), the members of our body (Romans 7:23), which is to be brought into subjection (1Corinthians 9:27)


How is it that to be absent from the body is to be present with the Lord? How shall sin enter the holy city? It never will. We must be 100% without sin in order to go beyond the Pearly Gates. So when does this happen? By His stripes we have been healed. Not waiting to be healed, we ARE healed already

Our INNER man has already been washed, cleansed, purified, sanctified. When we shed this body of death, the only thing left is a sinless being. That's why OT saints were in Sheol before He died. They had not been perfected yet. But they are with Him now, because they have been made holy. And we are made holy now in regeneration.

Then, in the resurrection, when Christ returns, He shall come with all His saints, having already been cleansed (Ephesians 5:25-26), and meet with our resurrected body (1Corinthians 15:42-58), which will then be raised imperishable. Then we will be presented totally blameless, and without spot (Ephesians 5:27)