The Daily Cycle of divine services is the recurring pattern of prayer and worship that punctuates each liturgical day in the life of the Orthodox Church.
Monasteries generally serve the entire cycle of services. Some cathedrals do, as well. Most parishes do not.
The Divine Liturgy is not itself a part of the Daily Cycle but is inserted into the cycle, usually after Orthros or the Sixth Hour. In some cases it is combined with Vespers. The service of Typika is related to the Divine Liturgy and is often celebrated on days the Divine Liturgy is not appointed.
The services of the Daily Cycle are usually contained in a bound collection called the Book of Hours, also known as the Horologion (Greek) or Chasoslov (Slavonic).
The Daily Cycle follows this pattern:
Although each service of the Daily Cycle has a particular time traditionally associated with it, in current practice the services are more commonly served together in one of three aggregations.
- The Evening Aggregate usually consists of Ninth Hour, Vespers, and Compline. It commences shortly before sunset.
- The Dawn Aggregate usually consists of Midnight Office, Orthros, and First Hour. It usually begins shortly before sunrise.
- The Midday Aggregate consists of Third Hour and Sixth Hour. The Divine Liturgy or Typika may be included in the Midday Aggregate.
On days when Great Compline is appointed (e.g., weekdays in Great Lent), it constitutes the entirety of the Evening Aggregate. Vespers is shifted to the Midday Aggregate.
On the eves of First Class Feasts, Second Class Feasts, and certain Third Class Feasts, a special aggregate, known as the All-Night Vigil, may be served. In such case, the other aggregations may be altered slightly (e.g., including Little Vespers in the Evening Aggregate). Although there is some variance in practice, the All-Night Vigil generally includes at least Great Vespers, Orthros, and First Hour.
Obligation to Recite
According to The Holy Catechism of Nicolas Bulgaris, pages 26 and 27, priests are obliged to read the divine office. In answer to the first question, "What is this preparation the priests undergo, that they may be worthy celebrants and ministers?" Nicolas Bulgaris says confess frequently, "read all his office," have ready the sacred vessels, and lastly, keep his mind orthodox and faithful. In answer to the third question, Nicolas Bulgaris says, "We said that he ought also to read all his service, although all priests, from the time that they receive the stamp of divine Ordination, whether then celebrate or do not, promise and are bound to read each day the whole of the service to the end of their life, and if they neglect it, fall into deadly sin." In answer to the forth question, "What is this Service?" Nicolas Bulgaris says, "Vespers, After Supper [Compline], Midnight Office, Mattins, Prime, Terce, Sext, and None, - altogether seven times a day."
- The Liturgikon: The Book of Divine Services for the Priest and Deacon, Bishop Basil (Essey) of Wichita (ISBN 0962419001)
- Website of the St. Raphael Clergy Brotherhood of the Diocese of Wichita and Mid-America
- The Great Horologion, Holy Transfiguration Monastery (ISBN 0943405084)
- Abridged Typikon, St. Tikhon’s Seminary
- The Holy Catechism of Nicolas Bulgaris, Constantinople, Patriarchal Press, 1861, reprinted 1961