2 When therefore Paul and Barnabas had no small dissension and disputation with them, they determined that Paul and Barnabas, and certain other of them, should go up to Jerusalem unto the apostles and elders about this question.
It is to be noted that the early believers, with much searching and great eagerness, discussed dogmas, and that they benefited to such an extent through their discussions and that the Antiochians did not hesitate to send [someone] to Jerusalem to inquire about the controversy. And yet their inquiry was not, in the first place, about the Godhead, or the providential incarnation of the Son, or the Holy Spirit, or angels, or powers, or heaven, or anything like this, but about circumcision, about the least part of a man’s genitals. They were aware of the fact that the words “a single iota and a single point of the law” were full of a great spiritual meaning. The Antiochian disciples were afraid to take authority, but they took so much thought even for questions that seemed to be trifling, seeing that those from Antioch sent Paul and Barnabas to consult those in Jerusalem, while the disciples from Jerusalem sent Judah and Silas back to Antioch with their letters.
How can he say in his letter to the Galatians, “I did not go up to Jerusalem to see those who were apostles before me, nor did I move”? We suggest this: in the first place because he had not gone up spontaneously but had been sent by others; and in the second place because he did not come in order to learn something but to persuade others. Indeed, from the beginning he held that opinion that the apostles approved later, namely, that it was not necessary to circumcise. Until that day, however, it had seemed to them that [Paul] was not worthy of faith, but they rather listened more to those who lived in Jerusalem. So [Paul] went up, not in order to gain what he had been ignorant of before but in order to persuade his opponents because those who were in Jerusalem agreed with them. He had recognized from the start what had to be done and needed no teacher. And he had a clear and sure idea, beyond any discussion, of what the apostles would have decreed after a long discussion. Since it had seemed opportune to the brothers that he might learn something about them, he went up not for himself but for them. Even though he says, “I did not go up,” we can explain that. He did not go up at the beginning of his preaching or in order to learn. And he means both these things when he says, “I did not go immediately in flesh and blood.” He did not simply say, “I did not go” but “I did not go immediately.”
And Paul does not say, What? Have I not a right to be believed after so many signs? but he complied for their sakes. But when he returned from thence, the doctrine also became more exact. For if they at Jerusalem enjoin no such thing, much more these have no right to do so.
They decided that Paul and Barnabas and some others from them should go up to the apostles and elders in Jerusalem, etc. About this ascension of his, Paul himself writes to the Galatians: Then, after fourteen years, I went up to Jerusalem with Barnabas, taking Titus along also, and I communicated to them the Gospel which I preach among the Gentiles (Galatians II); where the very number that he mentioned must be reckoned in years. For we know that the apostles Peter and Paul suffered martyrdom in the thirty-eighth year after the passion of the Lord, that is, in the last year of Nero, and that the blessed Peter sat upon the episcopal throne in Rome for twenty-five years. Now, twenty-five and fourteen make not thirty-eight but thirty-nine. Therefore, it follows that we believe the blessed Peter came to Rome in the same fourteenth year after the passion of the Lord, in which Paul conversed with him at Jerusalem, in the fourth year of Claudius Caesar; and likewise, unless I am mistaken, from this position it is proven that the blessed Apostle Paul came to faith in the same year in which the Lord suffered and rose again.
[AD 300] Ammonius of Alexandria on Acts 15:2