This deserting of Paul and Barnabas by John, is mentioned Acts 13:13. To the work; the work unto which the Spirit had called them, Acts 13:2, which was to offer life and salvation unto the Gentiles, and to gather them into the fold of Jesus Christ. This objection was very considerable, and ought to have weighed more than this John's propinquity, or nearness in blood, unto Barnabas.
Related Commentaries of Acts 15:38
Acts 15:38
38 But Paul thought not good to take him with them, who departed from them from Pamphylia, and went not with them to the work.