Chair of Peter
CHAIR OF PETER
As a theological expression, signifies the authority, especially the teaching authority, of the pope. The chair in which a bishop presides over his people was from early times regarded with respect as symbolizing his authority, since it was from his official chair (in which he sat, facing his people) that he gave the homilies by which he instructed his flock in the word of God. Hence the Feast of St. Peter's Chair, whether at Antioch or Rome, commemorated his authority there. Since the teaching power of the pope is not merely that of a bishop but that of the successor of St. Peter, the chair of Peter indicates the authoritative doctrinal power of the pope as the successor of St. Peter. This is the origin of the expression ex cathedra definition; such a papal pronouncement (very rarely made) is one in which the pope infallibly defines a doctrine that is irrevocably binding on all the faithful.
The Feast of the Chair of Peter is an ancient liturgical feast that is celebrated on February 22 in the Church's liturgical year.
[b. forshaw/eds.]