Catholic Encyclopedia (1913)/Orientation of Churches
According to Tertullian the Christians of his time were, by some who concerned themselves with their form of worship, believed to votaries of the sun. This supposition, he adds, doubtless arose from the Christian practice of turning to the east when praying (Apol., c. xvi). Speaking of churches the same writer tells us that the homes "of our dove", as he terms them, are always in "high and open places, facing the light" (Adv. Val., c. iii), and the Apostolic Constitutions (third to fifth century) prescribe that church edifices should be erected with their "heads" towards the East (Const. Apost., II, 7).
The practice of praying while turned towards the rising sun is older than Christianity, but the Christians in adopting it were influenced by reasons peculiar to themselves. The principal of these reasons, according to St. Gregory of Nyssa, was that the Orient contained man's original home, the earthly paradise. St. Thomas Aquinas, speaking for the Middle Ages, adds to this reason several others, as for example, that Our Lord lived His earthly life in the East, and that from the East He shall come to judge mankind (II-II, Q. lxxxiv, a. 3). Thus from the earliest period the custom of locating the apse and altar in the eastern extremity of the church was the rule. Yet the great Roman Basilicas of the Lateran, St. Peter's, St. Paul's (originally), St. Lorenzo's, as well as the Basilica of the Resurrection in Jerusalem and the basilicas of Tyre and Antioch, reversed this rule by placing the apse in the western extremity. The reasons for this mode of orientation can only be conjectured. Some writers explain it by the fact that in the fourth century the celebrant at Mass faced the people, and, therefore in a church with a western apse, looked towards the East when officiating at the altar. Others conjecture that the peculiar orientation of the basilicas mentioned, erected by Constantine the Great or under his influence, may have been a reminiscence of the former predilection of this emperor for sun-worship. In the Orient the eastern apse was the rule, and thence it made its way to the West through the reconstructed Basilica of St. Paul's, the Basilica of S. Pietro in Vincoli, and the celebrated basilica of Ravenna. From the eighth century the propriety of the eastern apse was universally admitted, though, of course strict adherence to this architectural canon, owing to the direction of city streets, was not always possible.
Kraus, Gesch. d. christ. Kunst, I (Freiburg, 1895); Realencyklopadie d. christ. Altertumer, s. v. Orientirung (Freiburg, 1886); Lowrie, Monuments of the Early Church (New York, 1901); Enlart, Manuel d'archeologie francaise, I (Paris, 1902).
MAURICE M. HASSETT