Romans 12 starts with a "I beseech you therefore" referring back to that end of Romans 11, just like Romans 11 started with "I say then" referring back to the end of Romans 10. Since Romans 11 wrapped up that the few Christian Jews are no different than the many Christian Gentiles, Romans 12 naturally takes the unitary Christianity and runs with it, or rather commands each Christian to do so individually and differently with thought to the highest level shared goal of serving God through Christ's "one body" earthly implementation of His one Christianity. The focus of the salvation-following (not necessary-for-salvation) "living sacrifice" presentation is on the saved person's acts — not on his or her birth, and not on any human merit in these acts but on their function as thankfulness returned to God. First and foremost, the undeserved gift of salvation was from God to us and all glory is therefore owed to God as the last verses of Romans 11 proclaim. He made it so that "everyone" (Rm. 11:32) began in need so that salvation would be entirely graceful, and since it is God's gift to us and not a repayment or even a merit-based reward, how absurd it is that anyone would think any less-than-merit trait of birth as favored under these New Covenant rules! God's Christian era in that sense is the ultimate equalizer of all men, in terms of their lack of self-credentials relative to God and salvation. All are equally unworthy regardless of even the most human-admirable of traits, and could not gain an advantage in this regard even by all of the works and accomplishments in the world. How much less by born-on traits such as Jewish race or Jewish nationality, which by this point in the letter are inconsiderable?
When therefore Paul begins discoursing on the lesser gifts given to Christians after they receive the gift of salvation, we of course see nowhere on his Romans 12 list being Jewish, but rather gifts referring to the performance of raceless roles or duties — prophecy, ministry, teaching, exhortation, giving, ruling, and showing mercy (Rm. 12:6-8). It would be very much in conflict with Paul's analogy of many members in the body of Christ, his examples of how those different members can benefit the body by acting on their various spiritual gifts, and the law of faith principle of how those members were included in the body of Christ in the first place, for anyone to instead assert that any members are providing any benefit based on extra-Christian membership in a special race. The body analogy's specification of "members" is shown by Paul's examples to instead represent the different natures of the various spiritual gifts. The point of which is to show that every Christian is to do his or her duty to serve Jesus Christ whether the role seems big or small in impact, or is different or unique — and that by preserving mind and body for the particular service. Then eventually, after appropriate development we might assume, the Christian is to mostly cast aside preparation for the actual doing of the specialized action that he or she was chosen to do. Paul seems to be saying, 'If a given spiritual gift is yours, then turn it into effective action while maintaining a proper attitude toward God and man.'
Recall verse 12:1 however that the purpose is a living sacrifice to God, in other words a life of devotion to the First Commandment of loving God, which peripherally includes loving our fellow man but does not include imitating and supporting the vices of our fellow man. We have this Second Commandment of Christ qualified appropriately by Paul in Romans 12:9 as "Let love be without dissimulation. Abhor that which is evil; cleave to that which is good." The rest of Chapter 12 and really the rest of the Romans Epistle is an expansion on this paradox of how we should love our fellow man but never compromise our love for God in so doing. The admonished abhorrence, or commanded hate, is for the evil thoughts and actions of other men as clarified in verse 12:17. It follows that if we are passionately and actively serving God then we are bound to violently conflict with the evil of the former because the two are essentially opposed. That Judaism, as it was then and will be foreverafter, is in its essence on the side of the Devil and in opposition to God, is a central theme of the Romans Epistle. Therefore we may grant opposing Jews that we will generally treat them according to Paul's advice in 12:20 that, "if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head." Christ told us the same that we Christians are to love our enemies. However, entirely consistent with Christ's prioritization of commandments also is Romans 12 verse 21, that we should "Be not overcome of evil, but overcome evil with good." We know from Romans 7 that if we do not overcome the evil of Judaism entirely — to the point of its total and complete death in us — that we cannot be an unadulterated part of that body of Christ in Romans 12 (Rm. 7:1-6, Rm. 12:5). Therefore we may conclude that any support on any level of the religion of Judaism in others is not to love them but to unadvisedly encourage their eternal damnation, and perhaps even to tempt our own fate if we as once-believers were to rather be overcome by their religious doctrine of Christ rejection. If we support the evil of false Judaism but maintain our Christian faith, we will be living not as the pure sacrifice of Romans 12 but as the sordid adulterer of Romans 7:3. That is not to say that we should chastise a Christian away from Christian faith if he or she is genuinely confused about this in small matters such as abstinence from meat consumption, per the example we will see in Romans 14. We know that Christ obliterated all such requirements, and this knowledge of the truth of the New Covenant is critical, however one is a religious adulterer only when he or she is using such worthless ritual in place of an aspect of Christ and His Christianity. If the mind of the confused is really trying to honor Christ by not eating meat, rather than to in any way demote Christ, then he or she is not in error in the choice of Christian religion but only in error as to knowledge of the lesser aspects of that Christian religion. On the other hand, if he is not eating meat because he thinks that following the Jewish Law is in any way required for salvation, or that reverence for Jewishness is any part of Christianity, then he is not honoring Christ but instead significantly shifting his allegiance and acknowledgement of binding importance away from Christ. Abstaining from meat for those anti-Christian reasons would indeed be injurious Judaism rather than harmless error within Christianity, and he would be the adulterer spoken of in Romans 7 — spiritually and ethically a danger to himself, to his children, and to all he influences.
