Kyrie eleison (kĭrˈēāˌ əlāˈēsŏnˌ, –sən) [key] [Gr., = Lord, have mercy], in the Roman Catholic Church, prayer of the Mass coming after the introit, the only ordinary part of the traditional liturgy said not in Latin but in Greek. It has nine lines: "Lord have mercy (thrice), Christ have mercy (thrice), Lord have mercy (thrice)." As the first invariable hymn, the Kyrie is often the first piece in a musical Mass. An English version is used in the Anglican liturgy and in the reformed Roman Catholic vernacular liturgy. The phrase Kyrie eleison used by itself is, of course, common in the Eastern rites, but without the phrase Christe eleison. The corresponding prayer in the Russian Orthodox church is often called a Kyrie.
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