Orientation of churches

Orientation of churches is the architectural feature by which the point of main interest in the interior, where the altar is placed, often within an apse, is towards the east (Latin: oriens). The main entrance is accordingly placed at the west end.

The first Christians faced east when praying, for which various explanations have been offered. In a tradition well established by the time of Christ, Jews in the diaspora would pray facing Jerusalem, which in most of the Roman Empire would have been to the East. Another explanation is that Christ's Second Coming would be on the clouds coming from the East: "For as the lightning cometh out of the east, and shineth even unto the west; so shall also the coming of the Son of man be." (Matthew 24:27). Due to this eastward posture of prayer, Tertullian (c. 160 — c. 220) says that some non-Christians thought they worshipped the sun.Origen (c. 185 — 253) says: "The fact that [...] of all the quarters of the heavens, the east is the only direction we turn to when we pour out prayer, the reasons for this, I think, are not easily discovered by anyone." Later on, various Fathers of the Church advanced mystical reasons for the custom.

At first, the orientation of the building in which Christians met was unimportant, but after the legalization of the religion in the fourth century, customs developed in this regard. These differed in East and West.

The Apostolic Constitutions, a work of eastern Christianity written between 375 and 380 AD, gave it as a rule that churches should have the sanctuary (with apse and sacristies) at the east end, to enable Christians to pray eastward in church as in private or in small groups. In the middle of the sanctuary was the altar, behind which was the bishop's throne, flanked by the seats of the presbyters, while the laity were on the opposite side. However, even in the East there were churches (for example, in Tyre) that had the entrance at the east end and the sanctuary at the west end. During the readings all looked towards the readers, the bishop and presbyters looking westward, the people eastward. The Apostolic Constitutions, like the other documents that speak of the custom of praying towards the east, do not indicate on which side of the altar the bishop stood for "the sacrifice".

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