Augustine of Hippo : If, when Paul had evangelized Arabia, he subsequently saw Peter, it was not so that he might learn the gospel from Peter himself (for then he would have seen him before) but so that he might enhance familial love by being with the apostles. — EPISTLE TO THE Galatians 8 [1B.1.15-19] Gaius Marius Victorinus : For if the foundation of the church was laid in Peter, to whom all was revealed, as the gospel says, Paul knew that he ought to see Peter. When he speaks of seeing Peter, it is as one to whom Christ had committed so much authority, not as one from whom he was to learn anything.… "How," [he implies], "could I learn this great knowledge of God from Peter in such a short time?" — EPISTLE TO THE Galatians 1.1.18 Jerome : He who had prepared himself for so long a time did not need any long instruction. And, though it seems excessive to some to investigate numbers in Scripture, yet I think it not beside the point to say that the fifteen days that Paul spent with Peter signifies [in late Judaic piety] the fullness of wisdom and the perfection of doctrine, seeing that there are fifteen psalms in a psalter and fifteen steps by which people go up to sing to God. — EPISTLE TO THE Galatians 1.1.18 Jerome : (Verse 18.) Then, after three years, I came to Jerusalem to see Peter. Not to look at his eyes, cheeks, and face, to see if he was thin or fat, if he had a hooked or straight nose, and if he covered his forehead with hair or (as Clement reports in his Periods) had baldness on his head. And I don't think it was the gravity of the Apostolic office that wanted to see something human in Peter after such a long three-year preparation. But she looked at him with these eyes, with which she seems to see him even now in her Letters. With his own eyes, Paul saw Peter, whom now by the wise and learned, Paul himself is seen. And if someone does not see this, let them join these facts with their superior understanding: that the apostles did not confer anything upon themselves. For even though Paul was told to go to Jerusalem, it was for the purpose of seeing the apostle, not for the purpose of learning, because he himself had the same author of preaching; but rather to show honor to the apostle who was before him. And I stayed with him for fifteen days. He did not lack for great instruction, as he had prepared himself so much time to see Peter. And although it may seem excessive to some, it is also fitting to observe the numbers that are in the Scriptures: nevertheless, I think it is not without reason that the fifteen days Paul spent with Peter signify complete knowledge and perfected doctrine. For there are fifteen songs in the Psalter, and fifteen steps by which the righteous ascend to sing to God, and stand in his courts. Moreover, Ezechias, having been granted fifteen years of life, deserves to receive a sign in the degrees (Isa. XXXVIII): and the solemnities of God begin on the fifteenth day (Exod. XII). Also, (because we follow a double understanding) therefore he adds fifteen days, to show that there was not a long time in which he could have learned anything from Peter; so that everything may be referred back to that meaning from which he began: that he was not taught by man, but by God. — Commentary on Galatians John Chrysostom : "Then after three years I went up to Jerusalem to visit Cephas." What can be more lowly than such a soul? After such successes, wanting nothing of Peter, not even his assent, but being of equal dignity with him, (for at present I will say no more,) he comes to him as his elder and superior. And the only object of this journey was to visit Peter; thus he pays due respect to the Apostles, and esteems himself not only not their better but not their equal. Which is plain from this journey, for Paul was induced to visit Peter by the same feeling from which many of our brethren sojourn with holy men: or rather by a humbler feeling for they do so for their own benefit, but this blessed man, not for his own instruction or correction, but merely for the sake of beholding and honoring Peter by his presence. He says, "to visit Peter;" he does not say to see, but to visit and survey, a word which those, who seek to become acquainted with great and splendid cities, apply to themselves. — Homily on Galatians 1 John Chrysostom : Worthy of such trouble did he consider the very sight of Peter; and this appears from the Acts of the Apostles also. For on his arrival at Jerusalem, on another occasion, after having converted many Gentiles, and, with labors far surpassing the rest, reformed and brought to Christ Pamphylia, Lycaonia, Cilicia, and all nations in that quarter of the world, he first addresses himself with great humility to James, as to his elder and superior. Next he submits to his counsel, and that counsel contrary to this Epistle. "Thou seest, brother, how many thousands there are among the Jews of them which have believed; therefore shave thy head, and purify thyself." Accordingly he shaved his head, and observed all the Jewish ceremonies; for where the Gospel was not affected, he was the humblest of all men. But where by such humility he saw any injured, he gave up that undue exercise of it, for that was no longer to be humble but to outrage and destroy the disciples. "And tarried with him fifteen days." To take a journey on account of him was a mark of respect; but to remain so many days, of friendship and the most earnest affection. — Homily on Galatians 1 Oecumenius : After three years, however, from the beginning of my preaching and teaching I returned to see Peter, I went up to see Peter, not to learn anything from him. For I was then preaching and proclaiming the gospel. "to visit Peter." See the humility. After so many and such great struggles he withdrew so that he might seem to be inferior to Peter. But so that he might remain honored as well, it was done on account of the honor which he conferred upon Peter. He said, "I stayed with him," yet I was not taught." — Commentary on Galatians Tertullian : But the fact is, having been converted from a persecutor to a preacher, he is introduced as one of the brethren to brethren, by brethren-to them, indeed, by men who had put on faith from the apostles' hands. Afterwards, as he himself narrates, he "went up to Jerusalem for the purpose of seeing Peter," because of his office, no doubt, and by right of a common belief and preaching. — The Prescription Against Heretics