No, he was to be purified as they were and he was being forced. The vow in Acts 18 is something completely different.
Again, being directed by James to take that action is not the same as being forced by James. Both vows involved cutting their hair, so they were both Nazarite vows.
Paul did not live according to the law. He taught against it as I have already proven.
Acts 21:24 says that he did that to show that he continued to live in accordance with the law. We must obey God rather than man, so you should be careful not to misinterpret something that is against obeying man as being against obeying God. Paul said that our faith does not abolish the law, but that it upholds the law (Romans 3:31).
And that was to fulfill the law and a new law and covenant to replace the old, just as Paul taught.
God has always been holy, righteous, and good, so He has always had such a conduct, and the law is holy, righteous, and good (Romans 7:12) because it is a reflection of His character and it is His instructions for how to have such a conduct. So the way to have such a conduct existed from the beginning and independently of any covenant. The Old Covenant can pass away, but God's character remains the same and the way to act in line with it remains the same, the only thing that changed was the laws in regard to the conduct of the priesthood.
Which is contrary to the rest of the content of your post, especially regarding Paul.
Paul was fully in favor of keeping the law.
The old law is gone, and we are not to obey it. We obey the new law of Christ.
Again, Christ was not in disagreement with the Father about what conduct we should have, but rather the law of Christ just is the way that he taught to obey the law, such as in Matthew 5, or by the example of perfect obedience that he set for us to follow, which we are told to follow (1 Peter 2:21-22).
There are only two laws. The old Sinai law of sin and death and the "law of Christ" which is the law of the Spirit of life!
Romans 7:22-24 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?
Paul said that he delighted in God's law and contrasted that with the law of sin and death. God did not command the law to bring sin and death, but to bring life abundantly.
1 Corinthians 9:19 For though I be free from all men, yet have I made myself servant unto all, that I might gain the more.
1 Corinthians 9:20 And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law;
1 Corinthians 9:21 To them that are without law, as without law, (being not without law to God, but under the law to Christ) that I might gain them that are without law.
1 Corinthians 9:22 To the weak became I as weak, that I might gain the weak: I am made all things to all men, that I might by all means save some.
Your interpretation maligns the character of Paul and turns him into the ultimate liar who felt free to lie to different groups of people about what he was saying to the other groups, free to lie in court, and free to openly admit that he lied and free to encourage others to lie, yet someone no one caught on to him. If he had been lying, then they would have easily been able to produce witnesses to his lies, but they couldn't because he wasn't lying. It would have been unacceptable to him to sin in order to spread the Gospel because that would have undermined the very message he was spreading. Rather, Paul was talking about giving up his rights and not taking a position over other people so that he could meet them where they were at. Paul never stopped identifying as a Jew, so he was not talking about pretending to be a Jew, but about following their customs. Note that in verse 21 he specifically said he was not without God's law, which was in a parallel statement to obeying the law of Christ.
Here again the two are compared.
James 1:25 But whoso looketh into the perfect law of liberty, and continueth therein, he being not a forgetful hearer, but a doer of the work, this man shall be blessed in his deed.
James 2:12 So speak ye, and so do, as they that shall be judged by the law of liberty.
It is also called "the law of liberty" because it is the opposite of the law of bondage, that same old law of sin and death.
The law of Moses is the law of Christ is the law of liberty. It is sin, which is the transgression of the law, that puts us in bondage, not the law that instructs us to be free from sin.
Romans 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.
Romans 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.
Paul says Christians are delivered from the law, because the old covenant law is dead.
Paul made it clear the next verse that the law was not sin. If we have been set free from all aspects of the law, then we have been set free to sin all we wanted because sin is lawlessness (1 John 3:4), however it is not the case that we have been set free to sin, but rather that we have been set free from sin. Our salvation is from sin, so our salvation is from lawlessness for the purpose of lawfulness. We have been set free from slavery to sin to become slaves of obedience (Romans 6:16). All OT Scripture, including the law, is God-breathed and is profitable for training in righteousness and equipping us to do every good work (2 Timothy 3:16-17) and we are made new creations in Christ for the purpose of doing good works (Ephesians 2:10).
Note that Paul specified that we were set free from what held us captive. The law held us captive when we transgressed it because the penalty of sin is death, but there is now no condemnation for those who are in Christ, so we have been set free from that so that we could be free to follow Christ, which involves following his example of obedience to the law. And again, like the woman in the example, she was not set free from having a holy, righteous, and good conduct, but was only set free from the penalty for not having such a conduct.
Romans 7:5-6 For when we were living according to our old nature, the passions connected with sins worked through the
Torah in our various parts, with the result that we bore fruit for death. 6 But now we have been released from this aspect of the
Torah, because we have died to that which had us in its clutches, so that we are serving in the new way provided by the Spirit and not in the old way of outwardly following the letter of the law.
Gill:
are become dead to the law, and that to them, as in Rom_7:6, and can have no more power over them than a law can have over dead persons, or a dead abrogated law can have over living ones. They are represented as "dead to sin", and "dead with Christ", Rom_6:2; and here, "dead to the law", as in Gal_2:19, and consequently cannot be under it; are out of the reach of its power and government, since that only has dominion over a man as long as be lives the law is dead to them; it has no power over them, to threaten and terrify them into obedience to it; nor even rigorously to exact it, or command it in a compulsory way; nor is there any need of all this, since believers delight in it after the inward man, and serve it with their minds freely and willingly; the love of Christ, and not the terrors of the law, constrains them to yield a cheerful obedience to it; it has no power to charge and accuse them, curse or condemn them, or minister death unto them, no, not a corporeal one, as a penal evil, and much less an eternal one. And the way and means by which they become dead to the law, and that to them is,
Indeed, being "dead to the law" does not refer to a status of being free from obeying it, but a status of being free from its power over us. Without any power over us to threaten or condemn us, the law remains simply instructions for how to have a holy, righteous, and good conduct, which is something that we should take inward delight in and serve freely and willingly, and which we are told to do as part of the New Covenant (1 Peter 1:14-16, 1 John 3:10, Ephesians 2:10). We are to have cheerful obedience to the law because of our love for Christ and our desire to follow his example. The law is spiritual (Romans 7:14) and it is those who have a carnal mind who do not submit to God's law (Romans 8:7).
that ye should be married to another; or "that ye should be to another", or "be another's"; that is, that ye should appear to be so in a just and legal way; for they were another's, they were Christ's before by the Father's gift, and were secretly married to him in the everlasting covenant, before he assumed their nature, and in the body of his flesh bore their sins, satisfied law and justice, paid their debts, and so freed them from the power of the law, its curse and condemnation, or any obligation to punishment; all which was done in consequence of his interest in them, and their marriage relation to him; but here respect is had to their open marriage to him in time, the day of their espousals in conversion; to make way for which, the law, their former husband, must be dead , and they dead to that, that so their marriage to Christ might appear lawful and justifiable; who is very fitly described by him,
Paul said in Romans 7:1 that he was speaking to those who knew the law, so he was using an example for the law to illustrate a point, rather than saying everything in the example represented something else. We can't be represented by the woman because we are dying to the law and it is her husband that dies, and we can't be represented by the husband because it is the woman who is free to get married to another. Paul was making the point that the death of her husband doesn't free her to disobey the law, but rather that it frees her from the penalty of disobeying the law, which is the point he is building to in Romans 8:1, and we are set free from that aspect of the law in the same way.