The versus populum altar
at San Giorgio in Velabro
There was an interesting line in letter to the New York Times this morning (July 19th). It had nothing to do with the question at hand: ad apsidem vs. versus populum for the celebration of the Mass-indeed, it was in the context of the role of historians in commenting on the current presidential election. But despite the context, the principle is the same. Historians keep our collective past in focus as an aid to determine our present (and future) choices. Whether it be our cultural history, our political history, or our ecclesiastical history we often fall victim to vague generalizations, popular myths, and incorrect data all if which leads to wrong conclusions.
Paris is one of my favorite cities and to see Paris from the air is a thrilling site. You can see the great ship of Notre Dame sailing eastwards up the Seine towards the rising sun. Other great ships—Saint Eustache, Saint Germaine des Pres, Saint Sulpice, Saint Gervais accompanied by a flotilla of smaller sanctuaries such as the Sainte Chapelle, Saint Julien le Pauvre, Saint Étienne du Mont, Saint Séverin, Saint Merry, and countless others following in its wake are a reminder that Parisian Churches face east. The same could be said for countless other cities in once-Catholic Europe—Prague, Vienna, Munich, Bamberg. But curiously, it cannot be said for Rome.
The orienting of the Churches was a widespread practice in the medieval world and, from the earliest days, an all-but-universal practice in the Christian East. In these churches the congregation—and usually the priest—stood facing the Rising Sun to offer the Eucharistic sacrifice which that Rising Sun signifies. But in Rome the ancient churches face every which way on the axis of the globe. Saint Peter’ and Saint John Lateran face west! (Of course, that does permit the bishop, when presiding versus Populum, at the main altar, to face east.) Saint Mary Major’s faces north. Saint Paul’s Outside the Walls on the Via Ostia is the only major basilica to face east—but even that church, in its original construction, faced west. 4th century San Martino ai Monti faces Northwest as does near by Santa Praessede. Also nearby, Santa Croce in Gerusalmme, also 4th century faces southwest. Santa Maria in Cosmedin faces southwest while nearby San Giorgio in Velabro faces almost due north. Across the Tiber, the very important 4th century basilica of Santa Maria in Trastevere faces almost due west. Santa Maria ad Martyres, better known as the Pantheon, faces south. The incontrovertible historical/architectural evidence is that the orienting of churches was not part of the tradition of the Roman Rite.
But the question of versus populum was not simply a matter of the direction of the church building. Today when visiting the four great papal basilicas one can see before the central altar a large open well sunk into the floor and into which pilgrims can descend to venerate the relics that lay beneath the altar. The position of this well, known as a confessio, makes it impossible for the presider to stand at the altar with his back to the people. The confessio is not limited to the basilicas but can be found in other churches where as well. Another common arrangement found at San Giorgio in Velabro and Santa Maria in Trastevere, features the altar flush with the front wall of an elevated presbyterium. Again, the space on the people’s side of the altar is nothing but open air and it is clear that these altars were designed for versus populum celebrations.
Altars built for Mass versus populum were not limited to Rome—they seem to have been common in Ravenna, seat of the Imperial exarch as well, despite the dependency of Ravenna on Constantinople where ad orientem was a very important theological principle. North of the Alps the ad orientem tradition took hold and it was only after the Reforms of the Council of Trent where many non-Roman features were introduced into the liturgy that the Roman Rite began celebrating with the priest facing away from the people. In Rome, the papal altars continued to face the people for the celebration of Mass and in those ancient churches that were built for Mass versus populum the practice continued without comment or interruption. In some churches such as San Martino ai Monti new altars were built that enabled the priest to celebrate ad apsidem, that is facing the rear wall of the church.
An interesting exception in Rome is the church of Santa Maria Sopra Minerva. The church was built when the papacy returned from Avignon and it was built by the Dominican friars. The Dominicans had their own rite and like most medieval rites oriented the churches whenever possible. Santa Maria Sopra Minerva was thus build facing east and presumably the altar was constructed for the ad orientem Mass.