It is probable that these verses are the close of the letter part of which is contained in chapters L–ix. Plummer and others regard it as the close of the severe letter. On the whole, the tone of this valediction seems to suit these chapters better.

12. Salute one another with a holy kiss is really a repetition of the exhortation to peace and harmony in the previous verse, and refers to the meeting for worship. As in the synagogue, the sexes would sit separately. The kiss is 'holy,' as signifying Christian brotherhood.

13. The Catholic doctrine of the Trinity must not be read back into this verse. There is no reference at all to the mutual relationship of Father, Son, and Holy Spirit. The grace of the Lord Jesus Christ comes first, and the order is significant. It was through the historical revelation of God in Christ that men experienced the Love of God and the new life in the Spirit–a divinely created life of fellowship between God and man, and therefore between man and man, irrespective of race, sex, or social position. This verse is the earliest of the few passages in the New Testament where, in a single sentence, the three elements of the Trinity are set alongside one another. It is significant that, thirty years after Jesus' death, His name, the Holy Spirit, and the name of God Himself should thus be brought together in one benediction. The benediction is a prayer, and the fully developed doctrine of the Trinity has its theological roots in adoration of Jesus Christ.