“And there arose a sharp disagreement, so that they separated from each other” (v39). Paul and Barnabas disagreed over John Mark’s inclusion in their ministry team. Unlike the debate about Gentiles, this was not a doctrinal issue, but instead a subjective pastoral issue. Not able to come to consensus, the men separated. Scripture never tells us who was “right,” though in his letters, Paul mentions both Mark and Barnabas positively (1 Tim 4:11; 1 Cor 9:6).
“Paul thought best …” (v38). Sometimes our “best” thinking does not produce agreement on secondary issues. In these cases, we can still focus on the gospel, speak positively about each other, and allow God to work.