Once Ash Wednesday arrives, people who are fortunate enough to be able to attend daily Mass just expect to see the priest dressed in the Lenten purple. But on Thursday, February 22nd, the church pauses from the purple and celebrates the Feast of the Chair of Saint Peter, Apostle. This feast brings to mind the mission of teacher and pastor conferred by Christ on Peter, and continued in an unbroken line down to Pope Francis. Although the feast celebrates a much deeper purpose, yes, there is a physical object known as “the Chair of St. Peter.” It is housed at the Vatican, at the back of St. Peter’s basilica. The term Chair of St. Peter means both the physical object—an ancient, ornamented chair—located in the apse of St. Peter’s Basilica, but more importantly, the spiritual authority that this chair represents.

This physical chair, known as the Cathedra Petri (Latin, “Chair of Peter”), is located in the apse of St. Peter’s Basilica. It is in the back of the chamber, behind the famous altar, on the far, back wall, below the stained glass image depicting the Holy Spirit as a dove. This ancient chair has been repaired and ornamented over time.

The Catholic Encyclopedia states of the original chair:

The seat is about one foot ten inches above the ground, and two feet eleven and seven-eighths inches wide; the sides are two feet one and one-half inches deep; the height of the back up to the tympanum is three feet five and one-third inches; the entire height of the chair is four feet seven and one-eighth inches.

The Encyclopedia goes on to state that there is no reason to believe that this piece of furniture is not the chair in which St. Peter himself sat. However, Pope Benedict was more reserved in offering such acclamation to the object.

The word “cathedra” means the established seat of the Bishop, placed in the mother church of a diocese, and thus the term used for the church of the bishop—the cathedral—where the chair of his office is located.

The first reading of the day exhorts not only ordained ministers, but all of us in leadership roles to shepherd the flock of Christ. Even the responsorial psalm is from the theme of the day, focusing on the relationship between God as the ultimate shepherd of our souls and each of us as the individual members of his flock. The gospel is the passage from which Christ states Thou are Peter and upon this rock…

We have been instructed that the pope is infallible (free from making a mistake) any time he speaks ex cathedra. This was declared by the First Vatican Council in 1870. So, does that mean the pope needs to wind his way to the ancient chair if he is to make such a decision? No, of course not. Although the pope’s infallible pronouncements are called ex cathedra (Latin, “from the chair”) statements, he does not have to be sitting in the physical chair (which is rather high off the ground in any case). He simply has to use the fullness of his authority as the successor of Peter, with the power of the Holy Spirit, to definitively establish a teaching on a particular matter pertaining to faith or morals. These declarations are referred to figuratively, as him speaking “from the chair” of St. Peter.

There are only two incidents of the pope using this authority. Both declarations are about Mary: Her Immaculate Conception (declared by Pope Pius IX in 1854 and grandfathered after the First Vatican Council’s declaration of papal infallibility in 1870) and her bodily Assumption into heaven (declared by Pope Pius XII in 1950).

While declaring someone a Saint (the act of canonization) is a declared fact, unchallenged once declared by the pope, it is not considered ex cathedra as this is not a matter of dogma of faith and morals.