Octoechos (liturgy)

The liturgical book called Octoechos (from the Greek: ἡ Ὀκτώηχος Greek pronunciation: [okˈtoixos]; from "eight" and "sound, mode" called echos; Slavonic: Осмѡгласникъ, Osmoglasnik from "eight" and "voice, sound") contains a repertoire of hymns ordered in eight parts according to the eight echoi (tones or modes). Originally created as a hymn book with musical notation in the Stoudios monastery during the 9th century, it is still used in many rites of Eastern Christianity. The hymn book has something in common with the book tonary of the Western Church. Both contained the melodic models of the octoechos system, but the tonary served simply for a modal classification, while the book octoechos is as well organized as a certain temporal of several eight week periods and the word itself means the repertoire of hymns sung during the celebrations of the Sunday Office.

Kathismata, odes or kontakia are set in a strict meter—a rhythm within a fixed number of verses as a strophe, a fixed number of syllables and accents as a verse. Despite the meter it is possible to arrange a complex poem like the prooimion of a Christmas kontakion composed by Romanos the Melodist which has its own history as a kontakion with its music and text, according to the simple melodic model of a sticheron in echos tritos of the Octoechos. In the current tradition the kontakion exists as well as avtomelon—as a model to recite stichera prosomoia which was as well translated into Old Church Slavonic.

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