Commentators really do not know. Numerous theories have been advanced over the centuries to explain why the Apostle decided to write to an ecclesial community he had never visited before, but commentators still disagree. Proposals range from Paul composing a compendium as an introduction to his controversial theology to Paul writing to Rome to constructively address the deteriorating relations between Gentile Christians and Jewish Christians (“the strong” vs. “the weak”). All of the proposals can find some textual support within the letter, but none alone seems to provide a convincing justification for the letter. Hence, as Frank Matera notes, commentators now tend to appeal to multiple reasons for the composition of the Epistle to the Romans.
Douglas Campbell, however, has recently proposed a theory that seems initially plausible to me: Paul is writing to the churches of Rome to address the same kind of problem that he had to address in his Epistle to the Galatians—the problem of Jewish-Christian teachers who advocate the submission of Gentile converts to Torah. These teachers are typically called Judaizers (though Campbell, following Louis Martyn, prefers to call them “the teachers”). The weakness of the theory is the lack of clear textual evidence. At no point does Paul explicitly state that his arguments are designed to refute the Judaizers, though Paul may be alluding to them in the letter’s conclusion:
I urge you, my dear family, to watch out for those who cause divisions and problems, contrary to the teaching you learned. Avoid them. People like that are serving their own appetites instead of our Lord the Messiah. They deceive the hearts of simple-minded people with their smooth and flattering speech. Your obedience, you see, is well known to all, and so I am rejoicing over you. But I want you to be wise when it comes to good, and innocent when it comes to evil. The God of peace will quickly crush the satan under your feet. (Rom 16:17-20)
These teachers may in fact be the same missionaries who attempted to undermine the Apostle’s ministry in the churches of Galatia. Paul’s reticence to name the false gospelers may thus be interpreted as a rhetorical and political move. Paul is a relative stranger to the Christians in Rome. He has no authority over them. No doubt they have heard about him and his teaching, and no doubt they have heard something of the many accusations that have been leveled against him by his opponents. Hence he chooses to present his gospel, which he wants the Romans to believe is the same gospel that they originally heard when they came to Christ, in a non-polemical way. Clearly it is important for him not to appear as if he is imposing his authority upon them. Clearly it is important for Paul to present himself and his theology in the best possible light. His message needs to be persuasive and his criticism of the Judaizers cogent; but he also needs to avoid unnecessary invective and any hint of demagoguery.
Campbell summarizes the similarities between Galatians and Romans:
The letters to the Galatians and the Romans share numerous motifs, questions, methods, terms, and arguments. They both emphasize apostleship (although Romans rather more subtly, as we have seen). Both speak of significant interactions with Jerusalem (although Galatians in retrospect, Romans in prospect). Both deploy a famous terminological antithesis between erga nomou [works of the law] and pistis [faith] framed by dikaio- terms, and this is a distinctive configuration among Paul’s letters. But both also supplement this with a marked use of participatory terminology and argumentation (a less distinctive usage). Baptismal motifs figure centrally in this participatory material, as does the Spirit, and some terminology of “Father” and “Son.” In these passages alone among Paul’s letters, Christians cry “Abba, Father.” The argument often proceeds by way of diatribal exchanges, and alternatively makes its case in relation to series of brief scriptural quotations. Abraham is a key figure in both letters, especially in relation to Genesis 15:6, but accompanying this text in both letters are Habakkuk 2:4 and Leviticus 18:5 (and these texts arguably supply much of the letters’ key terminology). The end of the age is also prominent, and a strong eschatological dualism (i.e., the presence of both ages, often intersecting within the Christian). The letter body of both epistles concludes with a fairly generalized paranetic section oriented toward the renewal of the Christian mind by the Spirit over against existence in the “flesh.” Paul’s exhortations then revolve at one point in both these subsections around the fulfillment of the law in the “love command” of Leviticus 19:18. Polemical comments about intruders and troublemakers are also apparent—comments that identify them as troublesome Jewish Christians.
This is a not inconsiderable list of similarities, and it has prompted numerous interpreters to posit not merely substantive and contingent similarity but temporal proximity. Suffice it now to state, however, that this extensive substantive overlap suggests that the same basic situation lies behind Romans and Galatians—false teachers promoting a certain teaching that Paul regards as deeply destructive. (The Deliverance of God, pp. 504-505)
We may surmise that St Paul has decided to write to the churches in Rome because he has heard that the false teachers have either arrived in Rome or perhaps are shortly expected to arrive there. He writes, therefore, to preempt their destructive work. Rome is a crucial strategic location in the Apostle’s plans. He hopes to visit the city in the near future and from that city launch his missionary work in Spain. It is important, therefore, for Paul to minimize the damage that these counter-missionaries might do in the imperial capital.
If Campbell’s thesis can be sustained, then new interpretive possibilities open up to us. It’s possible, for example, that portions of the letter that we have always assumed represent the beliefs of Paul in fact represent the beliefs of “the teachers.” We’ll keep this possibility open as we progress in our reading of Romans.