After some time Paul said to Barnabas, "Let's go back and visit each city where we previously preached the word of the Lord, to see how the new believers are doing." Barnabas agreed and wanted to take along John Mark. But Paul disagreed strongly, since John Mark had deserted them in Pamphylia and had not continued with them in their work. Their disagreement was so sharp that they separated. Barnabas took John Mark with him and sailed for Cyprus. Paul chose Silas, and as he left, the believers entrusted him to the Lord's gracious care. Then he traveled throughout Syria and Cilicia, strengthening the churches there.
— Acts 15:36-41 NLT
For years, I mourned this split between Paul and Barnabas over John Mark. Their division seems to contradict the spirit of unity that kept Jewish believers and new Gentile Christians in fellowship — what these two missionaries had just helped happen through the conference in Jerusalem. Over time, God has helped me realize that he has wired, gifted, and created his servants differently (1 Corinthians 12:4-6, 12-17). Barnabas was an encourager. He reclaimed others from the scrapheap and trained them to be valuable servants of Jesus. Barnabas had done this with Paul. He chose to do it again with John Mark. Barnabas remained faithful to both his missionary calling and his ministry of encouragement. Paul was driven to reach as many Gentile people in as many places as possible. Parting ways seemed inevitable. However, they did not allow their differences to split the brotherhood. Instead, the Lord doubled the number of mission teams and young missionaries as these two went their separate directions with their different approaches. Also, Mark developed to the point that he was valuable to Paul later, as the last two references in the Related Scripture Readings
indicate. We must reach out and include all people. That commitment to unity and mission was established at the Jerusalem conference. How to reach those people and recruit others to help, however, takes different approaches rooted in our personalities, giftedness, and calling from God.