4:18 The salutation by the hand of me Paul. Paul dictated his epistles to an amanuensis (Ro 16:22), but was wont to add a salutation in his own hand (Ga 6:11 2Th 3:17 1Co 16:21).
Remember my bonds. Three times this chapter he alludes to his chains, in Col 4:3,10,18. The thought is, Be willing to suffer for the gospel even as I do.
4:10-18 Paul had differed with Barnabas, on the account of this Mark, yet he is not only reconciled, but recommends him to the churches; an example of a truly Christian and forgiving spirit. If men have been guilty of a fault, it must not always be remembered against them. We must forget as well as forgive. The apostle had comfort in the communion of saints and ministers. One is his fellow-servant, another his fellow-prisoner, and all his fellow-workers, working out their own salvation, and endeavouring to promote the salvation of others. The effectual, fervent prayer is the prevailing prayer, and availeth much. The smiles, flatteries, or frowns of the world, the spirit of error, or the working of self-love, leads many to a way of preaching and living which comes far short of fulfilling their ministry. But those who preach the same doctrine as Paul, and follow his example, may expect the Divine favour and blessing.