The apostle Paul’s first visit to Jerusalem after seeing Christ on the Damascus Road lasted only fifteen days (Gal. 1:18). Acts 9:26–30 describes the same trip to Jerusalem we read about in Galatians 1:18–20, informing us that many disciples, early in Paul’s ministry, feared the one who once led the charge against them. It took Barnabas to convince the other disciples that Paul was truly a believer (Acts 9:27), although he only introduced Paul to Peter and James (Gal. 1:18–19). Since Peter and James were leaders in the church at Jerusalem, they would have told others the incredible truth that Paul had joined their side.
Yet the main explanation for Paul’s short stay is to be found in Acts 9:28–29. While in Jerusalem, the apostle preached the gospel, prompting some of the citizens there to seek his death. Thus, to save his life the believers in the city sent him back to Tarsus, his hometown and capital of the province of Cilicia (v. 30). While Paul does not mention the dangers he met, he does tell us that he left the Holy City for the regions of Syria and Cilicia (Gal. 1:21). Over the next fourteen years (or eleven, if the fourteen years includes the three years in Arabia, see v. 18) Paul ministered in these areas in relative obscurity (2:1), and we read very little about his work there. Still, we know that the churches of Judea outside of Jerusalem, though unable to recognize Paul on sight, rejoiced at the news that the one who once tried to destroy the faith had come to preach it (1:22–24).
This long ministry outside of Jerusalem proves that he could not have received the outline of his gospel from the apostles there. Moreover, since he stayed in the Holy City for a mere two weeks, during which he spent a lot of time preaching and teaching (Acts 9:28–30), Paul could not have received apostolic teachings that he would later pervert. Both facts effectively answer those Judaizing rumors in Galatia that called into doubt Paul’s apostolic calling.
Paul relied on no mere man for his apostolic call, but the Judean churches recognized the glory of God’s grace in his salvation (Gal. 1:24). Grace is central to Paul’s argument, and here he emphasizes its role, “saying ‘they glorified God in me’” (John Chrysostom, Ancient Christian Commentary, NT vol. 8, p. 16).