PAPAL CHAPEL. – This term designates those solemn sacred functions: Vespers, Matins, pontifical Masses and other sacred ceremonies that are performed by the Pope in person or with his assistance, or, in his absence, are conducted with the same ceremonial as if he were taking part.
These functions are now ordinarily and specifically assigned to the Sistine Chapel, so called because it was erected by Sixtus IV; but on the greatest solemnities they take place in the patriarchal basilicas or in other churches in honour of a more venerated saint. Such functions may be ordinary, if they follow a pre-established calendar; extraordinary, when they are ordered by the Pope on some special occasion. In both cases, on those days the Curia suspends the handling of business.
The Papal Chapel is composed of cardinals, patriarchs, archbishops and bishops, whether assisting at the Apostolic See or not, present in the Curia; the Prince Assistant to the Papal Throne; the four Prelates of the Flock; the assessors and secretaries of the Roman Congregations; the Grand Master of the Sacred Hospice; the Apostolic Protonotaries; the generals of the religious orders; the auditors of the Sacred Roman Rota; the clerics of the Apostolic Camera; the votants of the Signature; the consistorial advocates; the procurators of the religious orders and of the Sacred Apostolic Palace; secret chamberlains and secret chaplains, etc. The members of the Papal Chapel receive notice of their attendance through the Apostolic couriers.
In ancient times, divine service with singing was held daily in the papal palace, and on feast days bishops and cardinals celebrated the pontifical Mass according to the solemnity of the day, attended by the household of the palace, those of the cardinals, ambassadors, foreigners, etc. During Advent, Lent and certain solemnities, a sermon was also delivered in the Papal Chapel, entrusted to religious or ecclesiastics, sometimes even (especially in recent centuries) to students of the various ecclesiastical colleges. During the 19th century, the liturgical service in the chapel ceased to be daily and was limited to certain occasions and special solemnities; the sermon is now delivered on the Fridays of Advent and Lent and on Good Friday.