Romans 2:25-29 // Do The Circumcised Need to Keep Moses' Law

Based on Romans 2:25-29

25 For circumcision verily profiteth, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision. 26 Therefore if the uncircumcision keep the righteousness of the law, shall not his uncircumcision be counted for circumcision? 27 And shall not uncircumcision which is by nature, if it fulfil the law, judge thee, who by the letter and circumcision dost transgress the law? 

Circumcision is good if it is accompanied by humble devotion to God's moral law. It is not the circumcision itself that is advantageous, but the Jewish upbringing it represents as will be seen later. A circumcised person who breaks God's law is like an uncircumcised person who breaks God's law. The fact that he is circumcised does not make a difference in itself. Acts 7:51 describes heart uncircumcision as resisting the Holy Spirit; therefore submission to the Holy Spirit must be the meaning and fulfilment of circumcision.
The same works in reverse; if a person is physically uncircumcised but does keep God's moral law they have fulfilled the purpose of circumcision and there is no need for them to be circumcised; they can be considered "circumcised" or "Jews" already. The fact that people have been transformed by God's grace and lived by his law without being circumcised may be compared to the many who were circumcised but did not keep God law; at least ought to make physically circumcised sinners ashamed of themselves, and less inclined to judge.

28 For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: 29 But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
God's word tells us that real Jews are not defined by circumcision or any physical thing (like genes) but by a change inside. How can this be reconciled with the belief that modern Jews are still the subjects of major Bible prophecies that are to be fulfilled? God is not looking for a people that can be physically distinct, but rather morally distinct, however physical distinctions can be useful is reinforcing moral distinctions.
The greatest enemy of success is to try to please everybody. Try to please God, and if you can please others along the way, praise God!
You will make some enemies - hopefully not for being mean, that would not be pleasing God - Paul made some enemies, lots of them. Please God, only his ideas about what are important and what is right really count.

You can please God without being Jewish and without being circumcised, if you are not either don't try to become either. Those who are one or both of these already must not feel it makes us superior.
1 Stand fast therefore in the liberty wherewith Christ hath made us free, and be not entangled again with the yoke of bondage. 2 Behold, I Paul say unto you, that if ye be circumcised, Christ shall profit you nothing. 3 For I testify again to every man that is circumcised, that he is a debtor to do the whole law. 4 Christ is become of no effect unto you, whosoever of you are justified by the law; ye are fallen from grace. 5 For we through the Spirit wait for the hope of righteousness by faith. 6 For in Jesus Christ neither circumcision availeth any thing, nor uncircumcision; but faith which worketh by love. Galatians 5:1-6
Paul is writing to the church in Galatia. Are the Galatians he is writing to less than eight days old? Is he writing to those Jewish baby boys telling them they will be condemned if they let themselves get circumcised? Is he writing to unborn Jewish babies telling them they will be condemned from birth for being Jewish? No, no, no. But... there is a principle at stake. Adult Gentile men, Celts and Hellenes of Galatia are considering whether they should believe the teachers that are telling them they must be circumcised to be saved (Acts 15:1). They are thinking about the ordeal, and deciding that because they want to be sure they are saved, they are going to get circumcised. Paul is inspired by the Holy Spirit to write to them and in strong terms prevent them from carrying this out. By submitting to these teachers in circumcision, these adult men would be making a statement that the ceremonial law which included circumcision, which was first introduced to Abraham - not from Creation - and was fulfilled by faith and obedience to God; was still binding on the Christian, like the Ten Commandments. They would be trying to assure their salvation by fulfilling Moses' law - which was not given for that purpose - not by faith in Jesus. Such an act would demonstrate a lack of true faith in Jesus sufficient to compromise salvation. It is faith, working by love that brings salvation. There are good rules and better rules, but even the best rules do not enforce themselves. Obedience to God's Ten Commandments comes from faith working by love. Moses' Law was a set of good rules that helped facilitate the Jewish people to be ready for Jesus and to help them keep the Ten Commandments. We don't need them any more.

Circumcision is nothing; it won't condemn you or save you. If you do it to your sons let it be for some benefit un-related to salvation. If you want to do it to yourself, I can't think of any reason strong enough why you would if you were not doing it for salvation. That is why circumcising yourself indicates falling from grace.