Even in the geographical sphere, however, his achievements must not be underestimated; even in that sphere he labored far more abundantly than any other one man. His desire to plant the gospel in places where it had never been heard led him into an adventurous life which may well excite the astonishment of the modern man. The catalogue of hardships which Paul himself gives incidentally in the Second Epistle to the Corinthians shows that the Book of Acts has been very conservative in its account of the hardships and perils which the apostle endured; evidently the half has not been told. The results, moreover, were commensurate with the hardships that they cost. Despite the labors of others, it was Paul who planted the gospel in a real chain of the great cities; it was he who conceived most clearly the thought of a mighty Church universal which should embrace both Jew and Gentile, barbarian, Scythian, bond and free in a common faith and a common life. When he addressed himself to the Church at Rome, in a tone of authority, as the apostle to the Gentiles who was ready to preach the gospel to those who were at Rome also, his lofty claim was supported, despite the fact that the Church at Rome had itself been founded by others, by the mere extent of his labors.
The really distinctive achievement of Paul, however, does not consist in the mere geographical extension of the frontiers of the Church, important as that work was; it lies in a totally different sphere—in the hidden realm of thought.[6] What was really standing in the way of the Gentile mission was not the physical barriers presented by sea and mountain, it was rather the great barrier of religious principle. Particularism was written plain upon the pages of the Old Testament; in emphatic language the Scriptures imposed upon the true Israelite the duty of separateness from the Gentile world. Gentiles might indeed be brought in, but only when they acknowledged the prerogatives of Israel and united themselves with the Jewish nation. If premonitions of a different doctrine were to be found, they were couched in the mysterious language of prophecy; what seemed to be fundamental for the present was the doctrine of the special covenant between Jehovah and His chosen people.
This particularism of the Old Testament might have been overcome by practical considerations, especially by the consideration that since as a matter of fact the Gentiles would never accept circumcision and submit to the Law the only way to carry on the broader work was quietly to keep the more burdensome requirements of the Law in abeyance. This method would have been the method of "liberalism." And it would have been utterly futile. It would have meant an irreparable injury to the religious conscience; it would have sacrificed the good conscience of the missionary and the authoritativeness of his proclamation. Liberalism would never have conquered the world.
Fortunately liberalism was not the method of Paul. Paul was not a practical Christian who regarded life as superior to doctrine, and practice as superior to principle. On the contrary, he overcame the principle of Jewish particularism in the only way in which it could be overcome; he overcame principle by principle. It was not Paul the practical missionary, but Paul the theologian, who was the real apostle to the Gentiles.
In his theology he avoided certain errors which lay near at hand. He avoided the error of Marcion, who in the middle of the second century combated Jewish particularism by representing the whole of the Old Testament economy as evil and as the work of a being hostile to the good God. That error would have deprived the Church of the prestige which it derived from the possession of an ancient and authoritative Book; as a merely new religion Christianity never could have appealed to the Gentile world. Paul avoided also the error of the so-called "Epistle of Barnabas," which, while it accepted the Old Testament, rejected the entire Jewish interpretation of it; the Old Testament Law, according to the Epistle of Barnabas, was never intended to require literal sacrifices and circumcision, in the way in which it was interpreted by the Jews. That error, also, would have been disastrous; it would have introduced such boundless absurdity into the Christian use of the Scriptures that all truth and soberness would have fled.
Avoiding all such errors, Paul was able with a perfectly good conscience to accept the priceless support of the Old Testament Scriptures in his missionary work while at the same time he rejected for his Gentile converts the ceremonial requirements which the Old Testament imposed. The solution of the problem is set forth clearly in the Epistle to the Galatians. The Old Testament Law, according to Paul, was truly authoritative and truly divine. But it was temporary; it was authoritative only until the fulfillment of the promise should come. It was a schoolmaster to bring the Jews to Christ; and (such is the implication, according to the Epistle to the Romans) it could also be a schoolmaster to bring every one to Christ, since it was intended to produce the necessary consciousness of sin.
This treatment of the Old Testament was the only practical solution of the difficulty. But Paul did not adopt it because it was practical; he adopted it because it was true. It never occurred to him to hold principle in abeyance even for the welfare of the souls of men. The deadening blight of pragmatism had never fallen upon his soul.
The Pauline grounding of the Gentile mission is not to be limited, however, to his specific answer to the question, "What then is the law?" It extends rather to his entire unfolding of the significance of the Cross of Christ. He exhibited the temporary character of the Old Testament dispensation by showing that a new era had begun, by exhibiting positively the epoch-making significance of the Cross.
At this point undoubtedly he had precursors. The significance of the Cross of Christ was by no means entirely unknown to those who had been disciples before him; he himself places the assertion that Christ "died for our sins according to the Scriptures" as one of the things that he had "received." But unless all indications fail Paul did bring an unparalleled enrichment of the understanding of the Cross. For the first time the death of Christ was viewed in its full historical and logical relationships. And thereby Gentile freedom, and the freedom of the entire Christian Church for all time, was assured.