John Gill Bible Commentary

Salute one another with an holy kiss,.... Christian salutation is a wishing all temporal, spiritual, and eternal happiness, to one another; and which, as it should be mutual, should be also hearty and sincere, and this is meant by the "holy kiss"; the allusion is to a common custom in most nations, used by friends at meeting or parting, to kiss each other, in token of their hearty love, and sincere affection and friendship for each other; and is called "holy", to distinguish it from an unchaste and lascivious one; and from an hypocritical and deceitful one, such an one as Joab gave to Amasa, when, inquiring of his health, he took him by the beard to kiss him, and stabbed him under the fifth rib, Sa2 20:9; and as Judas, who cried, hail master, to Christ, and kissed him, and betrayed him into the hands of his enemies, Mat 26:49. I say, it is an allusion to this custom, for it is only an allusion; the apostle did not mean that any outward action should be made use of, only that their Christian salutations should not be mere complaisance, or expressed by bare words, and outward gestures and actions, either of the hand or mouth; but that they should spring from real love and true friendship, and be without dissimulation, hearty and sincere: the churches of Christ salute you. The Vulgate Latin, Syriac, Arabic, and Ethiopic versions read, "all the churches"; that is, in Greece, or in the neighbourhood where the apostle was, and who might know of his writing to this church, and thereby send their Christian salutations to it; or if they did not know of his writing, yet as he knew their sincere affections, and hearty good will to this church, and the members of it, he in their names sent greetings to them: this shows the communion of churches, and how they ought to wish and sincerely desire each other's welfare.