A still more tangible proof of this was that He who worked with Peter in the apostleship to the circumcision also worked with Paul among the Gentiles. The wondrous signs accompanying Saint Paul's preaching on his first missionary journey bore witness to this. He and Barnabas related these things both on the way to Jerusalem and in Jerusalem itself (cf. Acts 15).
In Paphos, on the island of Cyprus, he blinded Elymas, the Jewish sorcerer, for his stubborn resistance to the truth, which harmed the Gospel (cf. Acts 13:11). In Lystra he healed a crippled man who had never walked from birth. During his long stay in Iconium, the Lord confirmed the truth of the evangelical word, working signs and wonders by his hands (cf. Acts 14:3). After returning to Antioch, he told the Church of Antioch what God had done with him (cf. Acts 14:27).
It was evident that, just as all the Apostles preached everywhere, "the Lord working with them and confirming the word by the signs that followed" (cf. Mk 16:20), so Saint Paul also was not deprived of this cooperation from above in his preaching.
Once assured of this, the elder Apostles could not fail to see that Saint Paul was no self-appointed man. He had been chosen from above, since he was protected from above. Therefore one must suppose that, just as he then deliberately related in Jerusalem, at the Council, what signs and wonders God had worked among the Gentiles through the preaching of himself and Barnabas (cf. Acts 15:12), so here also, in the Epistle, he deliberately recalls it. Nothing persuades so strongly of the truth as testimony from above, when it is reliably known.
From this alone the Galatians could draw the conviction that his preaching, in the form and spirit in which he delivered it, was from God, who so visibly aided him in everything.
Thus Saint Paul, by the supernatural action of God's grace, was transformed from such a zealot of the Law into a man completely released from every bond of the Law. He was released in the conviction of his mind, in the feelings of his heart, and in deed itself. In this new state he was appointed to preach among the Gentiles the pure Gospel, wholly free from every admixture of Judaism. Therefore he is the Apostle of the Gentiles.
But why is Saint Peter called appointed to preach only to the Jews? Paul said, "The Gospel of the uncircumcision was entrusted to me, as the Gospel of the circumcision was to Peter." Yet the Lord commanded Saint Peter and all the other Apostles, "Go and teach all nations" (cf. Mt 28:19).
Saint Paul is speaking here of the state of the Apostles' activity as it was at the time touched on by his narrative. The course of the holy Apostles' activity may be represented in this way. At first they all labored in Jerusalem. When the Church had been firmly established in Jerusalem, they dispersed through the other cities and villages of Palestine. After founding Churches there also, they went throughout the whole world, each to the place assigned him by God.
In Jerusalem, for the completion of the ongoing work of converting the Jews, and for guidance in the perplexities of all the other Churches, Peter, John, and James were left. This was not James the son of Zebedee, but the brother of the Lord, the first presiding hierarch of the Church of Jerusalem. They remained there by common counsel and perhaps by indication from above.
This was the situation at the time of the Council. Peter and those with him were then occupied exclusively with ordering the Churches among the Jews. Saint Paul could say that the confirmation of faith among the circumcised had been entrusted to him. Peter is named alone here as representative of the others, being first among them.
Our Eastern interpreters, when explaining these passages, always say, "Peter and those with him." Saint Paul wished only to distinguish his own ministry from that of the others. Since Peter was the chief worker among the others before him, Paul compares himself with him alone.
Ambrosiaster writes: "He names only Peter and compares himself with him. As Peter received primacy in founding the Church from the Jews, so Paul presents himself as chosen to hold primacy in founding Churches from the Gentiles. Yet Peter also preached to the Gentiles when there was need, and Paul to the Jews. Both in fact did this. Still, full direction in preaching the faith among the Jews is acknowledged as Peter's, and full direction in preaching it among the Gentiles as Paul's. For this reason Paul calls himself a teacher of the Gentiles in faith and truth (cf. 2 Tim 1:11). Each of them received his appointment according to his strength."
Blessed Jerome sees in this distribution of apostolic labors a special, wise ordering of God's providence for the building of Christ's Church on earth.
"One and the same," he says through the mouth of Saint Paul, "entrusted to me the Gospel of the uncircumcision, and to Peter that of the circumcision. He sent me to the Gentiles, and appointed him to be in Judea. The Gentiles were not to be subjected to the pains of circumcision, which brought no benefit, nor compelled to abstain from foods to which they were accustomed. Nor could those who believed from among the Jews, being already circumcised, suddenly abandon the customs with which they had grown familiar, and in which they saw their superiority over the Gentiles. Therefore, by God's providence, one Apostle was given to the circumcised, who would condescend to the shadows of the Law, and another to the uncircumcised, who would offer the Gospel in the freedom of faith, without any admixture of the works of the Law. Thus there would be no hindrance to faith from either side, and no one would be deprived of faith in Christ because of circumcision or uncircumcision. This did not mean that Peter, who had been taught by a vision not to regard whether a man was Jew or Gentile, forgot this and thought that the Law must be fulfilled in addition to the grace of the Gospel. Rather, without refusing observance of the Law by condescension, he was gradually drawing the Jews away from their ancient customs of life. They could not be torn away from them suddenly. For this reason it is deliberately said, 'He who worked with Peter in the apostleship to the circumcision,' lest anyone think that Paul is reproaching Peter. Instead, having first encountered such praises, everyone would understand that Peter condescends to circumcision not without God's good pleasure. He does this precisely in order to preserve in the faith of Christ and in the Gospel those Jews entrusted to him. By this we are also given to understand that if Peter did not incur blame by observing for a time what was no longer necessary, lest he lose those entrusted to him, then Paul much more had to act according to the whole truth of the Gospel. He had to preserve what had been entrusted to him among the uncircumcision, lest the Gentiles, frightened by the yoke of the Law, be driven away from faith in Christ."