thumb|Farewell of [[Feast of Saints Peter and Paul|Saints Peter and Paul, showing the Apostles giving each other the holy kiss before their martyrdom. (Alonzo Rodriguez, 16th century, Museo Regionale di Messina).]]

The holy kiss is an ancient traditional Christian greeting, also called the kiss of peace or kiss of charity, and sometimes the "brother kiss" (among men), or the "sister kiss" (among women). Such greetings signify a wish and blessing that peace be with the recipient, and besides their spontaneous uses they have certain ritualized or formalized uses long established in Christian liturgy.

In the New Testament of the Christian Bible, the injunction for believers to greet one another with a holy kiss is given in five places in the New Testament. The early Christian apologist Tertullian wrote that before leaving a house, Christians are to give the holy kiss and say "peace to this house".

Among Conservative Anabaptists, such as the Conservative Mennonite churches and the Dunkard Brethren Church, the holy kiss is counted as an ordinance of the Church. As such, denominations of Conservative Anabaptism observe the practice of the holy kiss. It was also the custom in ancient Judea and practiced also by Christians. However, the New Testament's references to a holy kiss (, ) and kiss of love () transformed the character of the act beyond a greeting; furthermore, in the early Church, "the verbal exchange of 'peace' with a kiss appears to be a Christian innovation, there being no clear example in pre-Christian literature."—"Greet one another with a holy kiss" (Greek: ).

  • 1 Corinthians 16:20—"Greet one another with a holy kiss" (Greek: ).
  • 2 Corinthians 13:12—"Greet one another with a holy kiss" (Greek: ).
  • 1 Thessalonians 5:26—"Greet all the brothers with a holy kiss" (Greek: ).
  • 1 Peter 5:14—"Greet one another with a kiss of love" (Greek: ).

The early Christian apologist Tertullian wrote that before leaving a house, Christians are to give the holy kiss and say "peace to this house". The holy kiss was seen as an essential part of preparing to partake in the Eucharist:

Augustine's Sermon 227 is just one of several early Christian primary sources, both textual and iconographic (i.e., in works of art) providing clear evidence that the "kiss of peace" as practiced in the Christian liturgy was customarily exchanged for the first several centuries, not mouth to cheek, but mouth to mouth (note that men were separated from women during the liturgy) for, as the primary sources also show, this is how early Christians believed Christ and his followers exchanged their own kiss. For example, in his (), Latin priest-poet Sedulius condemns Judas and his betrayal of Christ with a kiss thus, "And leading that sacrilegious mob with its menacing swords and spikes, you press your mouth against his, and infuse your poison into his honey?"

The kiss of peace was known in Greek from an early date as (, 'peace', which became in Latin and peace in English). The source of the peace greeting is probably from the common Hebrew greeting ; and the greeting "Peace be with you" is similarly a translation of the Hebrew . In the Gospels, both greetings were used by Jesus – e.g. Luke 24:36; John 20:21, John 20:26. The Latin term translated as 'sign of peace' is simply ('peace'), not ('sign of peace') nor ('kiss of peace'). So the invitation by the deacon, or in his absence by the priest, "Let us offer each other the sign of peace", is in Latin: ("Offer each other peace" or "Offer each other the peace").

From an early date, to guard against any abuse of this form of salutation, women and men were required to sit separately, and the kiss of peace was given only by women to women and by men to men, with closed mouths. As such, denominations of Conservative Anabaptism observe the practice of the holy kiss. and among Spiritual Christians, where it is often called the 'kiss of peace', 'sign of peace', 'holy kiss' or simply 'peace' or 'pax'.

Anabaptism

The holy kiss is particularly important among many Anabaptist denominations, being counted as an ordinance of the Church.

Eastern Orthodoxy

In the Eastern Orthodox Church's Divine Liturgy of St. John Chrysostom, the exchange of the peace occurs at the midpoint of the service, when the scripture readings have been completed and the Eucharistic prayers are yet to come. The priest announces, "Let us love one another that with one accord we may confess—" and the people conclude the sentence, "Father, Son, and Holy Spirit, the Trinity, one in essence and undivided." At that point the kiss of peace is exchanged by clergy at the altar, and in some churches among the laity as well (the custom is being reintroduced, but is not universal). Immediately after the peace, the deacon cries "The doors! The doors!"; in ancient times, the catechumens and other non-members of the church would depart at this point, and the doors would be shut behind them. At that, worshippers then recite the Nicene Creed.

In the Eastern Orthodox Liturgy, the kiss of peace acts as a preparation for the Creed: "Let us love one another that we may confess[...] the Trinity."

In the early centuries the kiss of peace was exchanged between the clergy: clergy kissing the bishop, laymen kissing laymen, and women kissing the women, according to the Apostolic Constitutions. Today the kiss of love is exchanged between concelebrating priests. Such has been the case for centuries. In a few Orthodox dioceses in the world in the last few decades, the kiss of peace between laymen has attempted to be reinstituted, usually as a handshake, hugging or cheek kissing.

Another example of an exchange of the peace is when, during the Divine Liturgy, the Priest declares to the people "Peace be with all", and their reply: "And with your Spirit". More examples of this practice may be found within Eastern Orthodoxy, but these are the most prominent examples.

Catholicism

In the Catholic Church, the term now used is not "the kiss of peace", but "the sign of peace" or "the rite of peace". The General Instruction of the Roman Missal states: "There follows the Rite of Peace, by which the Church entreats peace and unity for herself and for the whole human family, and the faithful express to each other their ecclesial communion and mutual charity before communicating in the Sacrament." The priest says or sings: "The peace of the Lord be with you always", to which the people respond: "And with your spirit." Then, as stated in the Roman Missal, "if appropriate, the Deacon, or the Priest, adds: 'Let us offer each other the sign of peace.'"

In the Roman Rite, it is placed after the Pater Noster and before the Fractio Panis. Even within the Catholic Church, there are liturgical rites (the Ambrosian Rite and the Mozarabic Rite) in which it is placed after the Liturgy of the Word, before the gifts for consecration are put on the altar. The latter placing is influenced by the recommendation in Matthew 5:23–24 about seeking reconciliation with another before completing an offering at the altar. It was a practice in Rome itself at the time of Justin Martyr in the middle of the 2nd century. In the 3rd century the present placing was chosen not only in Rome but also in other parts of the West such as Roman Africa, where Saint Augustine understood it as related to the petition, "Forgive us our trespasses as we forgive those who trespass against us", in the Lord's Prayer and to the link between being in communion with the body of Christ understood as the Church and receiving communion with the body of Christ in the Eucharist.

Within the Roman Rite, instructions for the sign of peace differ depending on the liturgy being performed. In the Tridentine Mass, the sign of peace is given at Solemn Masses alone and is exchanged only among the clergy (unless emperors, kings or princes were present, in which case they, too, received the greeting by means of a pax). There also existed a custom in some places of the groom giving the Peace to the bride at the Nuptial Mass. However, unlike the present form of the Roman Rite, neither the bride nor the groom would pass the peace to anyone else.

In the Mass of Paul VI, the sign of peace is used at most Masses but is not obligatory. It is exchanged between all present in no prescribed order, except that "the Priest gives the sign of peace to a Deacon or minister."

The following are considered abuses by the Congregation for Divine Worship and the Discipline of the Sacraments:

  • introducing a "song of peace" to accompany the rite;
  • the faithful moving from their places to exchange the sign of peace;
  • the priest leaving the altar to give the sign of peace to some of the faithful;
  • expressing other sentiments, e.g. expressing congratulations, best wishes or condolences among those present at a wedding, funeral or other ceremony.

The gesture by which the sign of peace is exchanged is to be determined by the local episcopal conference. In some countries, such as the United States, the conference has laid down no rules, and the everyday handshake is generally used, while in other countries, such as India and Thailand, a bow is prescribed. A 2014 letter of the Congregation for Divine Worship and the Discipline of the Sacraments recommended that conferences choose gestures more appropriate than "familiar and profane gestures of greeting".