1 Peter 5:14

Greet ye one another with a kiss of charity Rather, a kiss of love. The tense of the Greek verb implies that it was to be done, not as a normal practice of the Church, but as a single act, probably when the Epistle had been read publicly, in token of the unity of feeling among all members of the Church. The practice would seem, from Romans 16:16; 1Co 16:20; 2 Corinthians 13:12, to have been common on such occasions in most of the Churches of the Apostolic age. The separation of the sexes when the Church met for worship, which was probably inherited from the Jewish synagogue, was a safeguard against the scandal which the practice might otherwise have occasioned. In the second or third century the "kiss of peace" became a stereotyped rubric in the Liturgies of the Church, the bishops and priests kissing each other on the cheek, and the laity following their example. Later on, in the thirteenth century, when the sexes were no longer separated, the practice was discontinued, but traces of it still survived in the use of the Osculatorium, or kissing token, known as the Pax(sometimes a relic, sometimes an ivory or metal tablet with sacred symbols cut on it), which was passed through the congregation, and kissed by each in turn. (Bingham, Eccl. Ant. xv. 3. Wetzer und Welte, Kirchen-Lexikon, Art. Friedenskuss.)

Peace be with you all that are in Christ Jesus There is something, perhaps, significant in the fact that while the final benediction of the Apostle of the Gentiles is "Grace be with you all" (Romans 16:24; 1Co 16:23; 2 Corinthians 13:14; and in all his Epistles), that of the Apostle of the Circumcision is the old Hebrew "peace," as in Matthew 10:13, in all the fulness of its meaning.