A cathedra (Latin, "chair", from Greek, kathedra, "seat") is the chair or throne of a bishop. It is a symbol of teaching authority in the Orthodox Church. Cathedra is the Latin word for a chair with armrests. Its Roman connotations of authority reserved for the Emperor were adopted by bishops after the fourth century. In this sense, cathedra is sometimes referred to as a "bishop's throne”. A church in which a cathedra is installed is called a cathedral — the seat of a particular church called a diocese or eparchy. The term cathedra is applied also to the see of a bishop.
The traditional position of the cathedra was in the apse behind the altar table, which was the position of the magistrate in the apse of the Roman basilica that provided the model type—and sometimes the actual structures—for early Christian basilicas. Originally the bishop’s cathedra stood in the center of the apse, flanked on either side, though on a lower plane, by benches for assisting priests. During the early centuries of Christianity it was customary for the bishop to deliver his sermon or homily while seated in his chair facing the congregation.
Today, cathedrals have a throne for the bishop in the apse behind the altar table, with seats for the priests to sit to either side of him (only bishops and priests are permitted to sit in the altar; deacons and the lower clergy must stand). This location is referred to as the High Place and represents the presence of Christ presiding over the services, even when the bishop is not present. For this reason, the High Place often has an icon of Christ placed above the seat and on the iconostasis seated in an armed chair. The bishop will only ascend the High Place during the Divine Liturgy, at the Trisagion (at other times, if he sits in the sanctuary, a seat will be prepared for him off to the side). For this reason, the consecration of a bishop takes place at the Trisagion, so that he may ascend the High Place for the first time as a bishop during the Liturgy at which he is consecrated.
Another throne for the bishop is located in the nave of the church:
- In the Greek practice, this is normally located along the southern wall of the church, on the kliros. In this style, it is one of the monastic choir stalls (kathismata), only more elaborately carved, usually at the top of three steps, and with a canopy above it. During the Divine Liturgy, the deacon will ascend this throne to read the Gospel, facing west.
- In the Russian practice, the kafedra is a large square platform set in the very center of the nave, with a moveable chair or faldstool placed on it. This arrangement is a remnant of the ancient bema (Greek: amvon), borrowed from the Jewish synagogue, which stood in the center of the synagogue in ancient times. During the Russian liturgy, the deacon will stand on this platform, facing east, to read the Gospel.
Although an hegumen (abbot) does not have a cathedral, he may have a similar chair, reserved for him on the kliros of his monastery, likewise symbolic of his authority, The hegumen's kathisma would be simpler than the one for the bishop, sometimes raised atop two steps, located to the side of the bishop's throne.