Romans 13:14
Pretty much wraps it up.
Unbelievers cannot choose either (a) to put on Christ or (b) to walk by the flesh and fulfill its lusts. They cannot put on Christ at all while unbelievers because flesh is all they have.
This is all to, for and about those in Christ.
I couldn't agree more.
Allow me a ramble...
The same truth is in Ephesians - that of the need to make no provision for the flesh.
Of the need to put off the old, and put on the new...daily.
Another aspect of which is described in Galatians - that of what attempting to serve God as one did under the Law only sets off in one - the lusts of the flesh.
Thus, why the Galatians had ended up at one another's throats - the very enmity that legalism results in.
Anyway...
Romans 13:12 The night is far spent, the day is at hand: let us therefore cast off the works of darkness, and let us put on the armour of light. 13:13 Let us walk honestly, as in the day; not in rioting and drunkenness, not in chambering and wantonness, not in strife and envying. 13:14 But put ye on the Lord Jesus Christ, and make not provision for the flesh, to fulfil the lusts thereof.
Ephesians 4:21 If so be that ye have heard him, and have been taught by him, as the truth is in Jesus: 4:22 That ye put off concerning the former conversation the old man, which is corrupt according to the deceitful lusts; 4:23 And be renewed in the spirit of your mind; 4:24 And that ye put on the new man, which after God is created in righteousness and true holiness.
There is that, but there is also the fact taught in Romans 7, that putting oneself back under the Law as a hoped for means of the above...only backfires...
Galatians 5:16 This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh. 5:17 For the flesh lusteth against the Spirit, and the Spirit against the flesh: and these are contrary the one to the other: so that ye cannot do the things that ye would. 5:18 But if ye be led of the Spirit, ye are not under the law.
The Spirit would never lead the Believer to put himself back under the very system that had been meant to set off the flesh "that sin might appear" crystal clear to the individual for what it is - "sin."
Romans 7:13 Was then that which is good made death unto me? God forbid. But sin, that it might appear sin, working death in me by that which is good; that sin by the commandment might become exceeding sinful.
Romans 7:4 Wherefore, my brethren, ye also are become dead to the law by the body of Christ; that ye should be married to another, even to him who is raised from the dead, that we should bring forth fruit unto God. 7:5 For when we were in the flesh, the motions of sins, which were by the law, did work in our members to bring forth fruit unto death. 7:6 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.
As Paul had had to remind Peter when the latter's action had basically amounted to telling those Gentiles that they needed to put themselves under the very system that Paul had taught them was no longer, as it had accomplished what it had been meant to accomplish - set off the bondage of sin in the flesh, that the sinner might see himself for what he was - a sinner in need of a Saviour, and thus, no longer under the Law for righteousness this side of having trusted said Saviour's righteousness...
Galatians 2:14 But when I saw that they walked not uprightly according to the truth of the gospel, I said unto Peter before them all, If thou, being a Jew, livest after the manner of Gentiles, and not as do the Jews, why compellest thou the Gentiles to live as do the Jews? 2:15 We who are Jews by nature, and not sinners of the Gentiles, 2:16 Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be justified. 2:17 But if, while we seek to be justified by Christ, we ourselves also are found sinners, is therefore Christ the minister of sin? God forbid. 2:18 For if I build again the things which I destroyed, I make myself a transgressor. 2:19 For I through the law am dead to the law, that I might live unto God. 2:20 I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me. 2:21 I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.
Both, the Israel of God, and the Body of Christ, were now no longer under the Law FOR righteousness.
Rather, the Israel of God now kept it because another aspect of it was its identifying them as the Israel of God in the sight of the nations.
Deuteronomy 4:5 Behold, I have taught you statutes and judgments, even as the LORD my God commanded me, that ye should do so in the land whither ye go to possess it. 4:6 Keep therefore and do them; for this is your wisdom and your understanding in the sight of the nations, which shall hear all these statutes, and say, Surely this great nation is a wise and understanding people. 4:7 For what nation is there so great, who hath God so nigh unto them, as the LORD our God is in all things that we call upon him for? 4:8 And what nation is there so great, that hath statutes and judgments so righteous as all this law, which I set before you this day?
Zechariah 8:23 Thus saith the LORD of hosts; In those days it shall come to pass, that ten men shall take hold out of all languages of the nations, even shall take hold of the skirt of him that is a Jew, saying, We will go with you: for we have heard that God is with you.
Isaiah 2:3 And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem.
In this, the Israel of God also being free from the negative aspect of the Law - it's unbearable burden - they now lived "after the manner of the Gentiles" - "saved even as they" (Acts 15:11) - "even we have believed in Jesus Christ, that we might be justified by the faith of Christ" Paul had had to remind Peter.
But they were His "by sight" people; the Law identifying them as such.
Paul, given his experience with these issues with other assemblies elsewhere long his vast understanding of such issues by the time he writes that Jew-Gentile assembly of Body members at Rome; anticipates the many various issues that might come up, and addresses them.
In this, Romans is almost a Bible all by itself...