Typikon

Typikon (or typicon, pl. typica; Greek: Τυπικόν , "that of the prescribed form"; Slavonic: Тvпико́нъ Typikonə or уставъ, ustavə) is a liturgical book which contains instructions about the order of the Byzantine Rite office and variable hymns of the Divine Liturgy.

The ancient and medieval cathedral rite of Constantinople, called the "asmatikē akolouthia" ("sung services"), is not well preserved and the earliest surviving manuscript dates from the middle of the eighth century. This rite reached its climax in the Typicon of the Great Church (Agia Sophia) which was used in only two places, its eponymous cathedral and in the Basilica of Saint Demetrios in Thessalonica; in the latter it survived until the Ottoman conquest and most of what is known of it comes from descriptions in the writings of Saint Symeon of Thessalonica.

Typica arose within the monastic movements of the early Christian era to regulate life in monasteries and several surviving typica from Constantinople, such as those of the Pantokrator monastery and the Kecharitomene nunnery, give us an insight into ancient Byzantine monastic life and habits. However, it is the typicon of the Holy Lavra of Saint Sabbas the Sanctified near Jerusalem that came to be synthesized with the above-mentioned cathedral rite and whose name is borne by the typicon in use today by the Byzantine Rite.

In his Lausaic History, Palladius of Galatia, Bishop of Helenopolis, records that the early Christian hermits not only prayed the Psalms, but also sang hymns and recited prayers (often in combinations of twelve). With the rise of Cenobitic monasticism (i.e., living in a community under an Abbot, rather than as solitary hermits), the cycle of prayer became more fixed and complex, with different ritual practices in different places. Egeria, a pilgrim who visited the Holy Land about 381–384, recorded the following:

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