Katabasia

Katabasia or Katavasia (Greek καταβασία, from καταβαίον, "go down") is a type of hymn chanted in the Eastern Orthodox Church and those Eastern Catholic Churches which follow the Byzantine Rite.

The katabasia is an irmos that is sung at the end of an ode of the canon. The katabasia is chanted by the choir, who descend from their seats (kathismata) and stand on the floor of the church to sing it, whence its name. Katabasia are chanted at Matins and sometimes during other Divine Services such as Compline. They are also found at other occasional services such as the Mystery of Unction or funerals.

At Matins, on ordinary weekdays, only Odes 3, 6, 8 and 9 have katabasia. On Sundays and higher-ranking feast days, there will be a katabasia at the end of each ode (these are called Festal Katabasia). Most of the other services which use katabasia will have them only after the 3rd, 6th, 8th and 9th odes.

On ordinary weekdays (that is, days which do not fall on a Sunday or higher-ranking feast day), the irmos from the canon being chanted is repeated at the end as katabasia. When several canons are tied together, as is normally the case at Matins, only the irmos of the first canon is chanted, subsequent irmoi being omitted. The irmos of the final canon in the string will be chanted at the very end of Odes 3, 6, 8 and 9 as katabasia.

On Sundays and feast days, Festal Katabasia are used at the end of each ode. These are not necessarily the same as the irmoi of the canon. Which particular Festal Katabasia are used will depend upon the liturgical season. The festal Katabasia are used in anticipation of a Great Feast, and throughout its Afterfeast. During the rest of the year, the Festal Katabasia to the Theotokos (Mother of God) are used.

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