Why this particular epistle should have this character of a systematic treatise is not hard to see. St. Paul was reaching the end of his great controversy for the catholicity of the Gospel, against the Judaizers--that is, for the equal position of Gentiles and Jews in the Church, and against the obligation upon the Gentiles of circumcision and the ceremonial law. That controversy was the occasion of the apostolic conference at Jerusalem, which is described both by St. Luke in the Acts[8] and, from the point of view of St. Paul's own 'apology,' in the Epistle to the Galatians[9]. It is felt at its whitest heat in that intensely concentrated and passionate epistle. But by the time that the Epistle to the Romans came to be written the controversy was quieting down. The victory of Catholicism over Judaism was as good as won. The great principle of justification by faith, not by works of the law, had developed itself lucidly {5} and clearly in St. Paul's mind, and flowed out in our epistle in an ordered sequence of thought, rich, profound, and mature. And there were special reasons why it should have been expressed in writing at this moment, and to the Roman Christians. Though the heat of the conflict inside the Church was over, the fierce hostility of many of the Jews, both within and without the Church, to St. Paul personally was by no means past. Now St. Paul was on his way up to Jerusalem with the money collected in the Gentile churches for the poor brethren there. He attached great importance to this expression of Gentile goodwill, and almost more importance to its acceptance at his hands by the Jerusalem Christians[10]. It was to be a link of mutual, practical love to bind the divergent elements in the Church together. But he felt, and as experience showed rightly, that his enterprise would be attended with great peril to his life. This epistle therefore, like his speech at Miletus, has something of the character of 'last words[11].' He is in writing it committing to the future the fruits of his labours, so far as they can be expressed in a doctrine, at a moment when he feels that their continuance is being {6} seriously imperilled. And this summary of his life's teaching in its most characteristic aspect is most fitly addressed to the Christians of the great city which was the centre of the then world. St. Paul already conceived of Christianity as, in prospect at least, the religion of the empire. It was vastly important, therefore, that the capital should know it and hold it in its full glory and richness. He himself, if he escaped safe through the visit to Jerusalem, was bent on immediately going thither and securing this great end by his personal ministry[12]. But he could not depend on the future. He must seize the golden moment--buying up the opportunity at least by a letter.