Then three years later I went up to Jerusalem to become acquainted with Cephas, and stayed with him fifteen days.Galatians 1:18(NASB)
Paul's authority was challenged by Judaisers in Galatia, who distorted the truth of the gospel by persuading believers to add works of the law to the gospel of grace, and so he presented a series of arguments in defence of his message, ministry, apostleship, and doctrine.
One by one, Paul listed the evidences supporting his apostolic authority and detailing events following his conversion on the road to Damascus - when he was commissioned as Christ's apostle to the Gentiles. He did not immediately consult with the other apostles in Jerusalem, but travelled to Arabia where he received direct revelation from the Lord Jesus Himself: "Then three years later," he writes, "I went up to Jerusalem to become acquainted with Cephas (i.e. Peter), and stayed with him fifteen days."
Paul's calling and experience was very different from the apostles in Jerusalem. They had been with Jesus from the beginning. They had walked with Him along the shores of the Galilee and listened to His astonishing claims. They had witnessed His mighty miracles and been supernaturally endowed to heal the sick, raise the dead, cast out demons, and preach the gospel of the kingdom to the lost sheep of the house of Israel.
During the time that Peter was called to be a fisher-of-men, he developed a deep love for his Lord and confessed, "you are the Christ, the Son of the living God." Paul, on the contrary, kept company with the proud Pharisees that sought to destroy Jesus, and following His crucifixion became the chief persecutor of Christ's followers.
Paul received no theological input from the other apostles following his conversion. He was given direct revelation from the glorified Lord Jesus during his early years in the Christian faith. And yet, when he travelled to Jerusalem "after three years," we discover in Acts, and elsewhere, that the message Paul was given for the Gentiles and the doctrine he taught to the churches in Galatia, was the same message of the grace of God that the apostles understood - where there is neither Jew nor Greek, slave nor free, male nor female, colour nor nationality - for all are all, one in Christ and members of His mystic Body.
I am sure that Paul had a meaningful and encouraging time with Peter during that fifteen-day visit. I am sure they discussed all the things that Christ had revealed to Paul during his years in Arabia and the experiences Peter had during Christ's sojourn on earth. No doubt they rejoiced in the indwelling ministry of the Holy Spirit and were excited and encouraged that the doctrine of Peter harmonised with that which Paul taught.
I am sure they discussed the importance of salvation being a gift of God, through faith in Christ and the uniting of Jewish and Gentile believers in the Body of Christ and I am sure they came to an understanding that Jewish believers are saved in the same way as Gentiles believers, for we read: "we are also saved through the grace of the Lord Jesus, in the same way that Gentiles are," without the encumbrances of the Jewish religious system.
It must have been quite a challenge for both Peter and Paul to disengage themselves from the gospel of the kingdom and their strict religious system, with its rules, rituals, and regulations. It must have been fairly difficult to begin to teach the gospel of the grace of God where we have such liberty in Christ.
Peter admits in his second epistle, that he found some of Paul's writing hard to understand and had to be challenged when he slipped back into certain Jewish rituals... while Paul became increasingly ostracised and harshly treated by many of his Jewish brethren who refused to understand that the promised kingdom of heaven was postponed because of Israel's unbelief and, for a season, believing Jews and believing Gentiles would unite as one Body. Together, as the Body of Christ, they would go into all the world and preach the gospel of grace to lost sinners - both Jews and Gentiles.
Heavenly Father, thank You for the ministries of both Peter and Paul and the careful way You have used their teachings to guide us into all truth. Thank You that we are not encumbered with the Jewish legal system with its numerous rituals and regulation. Thank You that by Your grace, Jew and Gentile have been united together in the mystical Body of Christ and are one in Him. May we share the gospel of grace with lost sinners for Your greater praise and glory. Thank You that the day is coming when the gospel of the kingdom will once again be preached throughout the world and Jesus will return to set up His kingdom on earth. This I pray in Jesus' name, AMEN.