Cathedra

A cathedra (Latin, "chair", from Greek, καθέδρα kathédra, "seat") or bishop's throne is the seat of a bishop. It is a symbol of the bishop's teaching authority in the Catholic Church, the Orthodox Church, and the Anglican Communion churches. Cathedra is the Latin word for a chair with armrests, and it appears in early Christian literature in the phrase "cathedrae apostolorum", indicating authority derived directly from the apostles; its Roman connotations of authority reserved for the Emperor were later adopted by bishops after the 4th century. A church into which a bishop's official cathedra is installed is called a cathedral.

The Joint International Commission for Theological Dialogue Between the Catholic Church and the Orthodox Church makes use of the term cathedra to point out the existence of a bishop in each local church, in the heart of ecclesial apostolicity.

The definitive example of a cathedra is that encased within the Triumph of the cathedra Petri designed by Gian Lorenzo Bernini in 1657 and completed and installed in 1666. As early as the 8th century, an ancient wooden chair overlaid with ivory plaques depicting the The Twelve Labours of Heracles and some of the constellations was venerated as the episcopal chair of St. Peter. It is a Byzantine throne with framed fragments of acacia wood encased in the oak carcass and reinforced with iron bands. It was long believed to have been used by the Apostle Saint Peter, but the Vatican recognises that the chair was a gift from Holy Roman Emperor Charles the Bald to Pope John VIII in 875. Several rings facilitated its transportation during processions. Pope Alexander VII commissioned Bernini to build a monument to display this relic in a triumphant manner. Bernini's gilded bronze throne, richly ornamented with bas-reliefs, encloses the relic. On January 17, 1666 it was solemnly set above the altar of Saint Peter's Basilica in Vatican City. Greater than life-sized sculptures of four Doctors of the Church form an honor guard: St. Ambrose and St. Athanasius on the left, and St. John Chrysostom and St. Augustine on the right.

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