liturgy, Christian [Gr. leitourgia = public duty or worship] form of public worship, particularly the form of rite or services prescribed by the various Christian churches. In the Western Church the principal service centered upon the Eucharistic sacrifice, but with the Protestant Reformation, the reformers generally rejected the idea of sacrifice and shifted toward the sermon as the focus of formal worship. They also adopted vernacular speech. The liturgy of the Roman Catholic, the Orthodox Eastern, and some other groups centers upon the Eucharist. In the Roman Catholic Church there are nine rites with distinctive liturgies (in various languages). The Orthodox Eastern Church has several liturgies. The ancient liturgies of the East are classified as Antiochene or Syrian (with modern liturgies in Greek, Old Slavonic, Romanian, Armenian, Arabic, and Syriac) and Alexandrine or Egyptian (with liturgies in Coptic and Ethiopic). The liturgies that arose in the West are classified as either Gallican (including the Celtic, Mozarabic, and Ambrosian) or Roman, both using Latin. In the 8th cent. the Gallican was largely superseded by the Roman, which is the principal liturgy of the Roman Catholic Church today. The language was Latin until the vernacular liturgy was introduced following the Second Vatican Council. In a broader sense, liturgy includes the divine office (given in the breviary) and also services other than the Mass. In the 20th cent. there has been a movement, called the liturgical movement, for purification and renewal of liturgy. Most of its demands were met in the Roman Catholic Church by the liturgical reformation directed by the Second Vatican Council, including the use of vernacular languages in the Mass, participation of the laity in public prayer, and an emphasis on music and song. In the Protestant churches a similar liturgical movement has gained much ground, urging the formulation and reform of service and wider awareness of the value of form itself.
See E. B. Koenker, The Liturgical Renaissance in the Roman Catholic Church (1954, repr. 1966); J. A. Jungmann, The Mass of the Roman Rite (1959); D. Attwater, The Christian Churches of the East (2 vol., rev. ed. 1961); T. Klauser, A Short History of the Western Liturgy (tr. 1969).