Location
The nave is the main body of the church where most of the worshippers stand, and the sanctuary is the area around the altar, east of the nave. The sanctuary is usually one to three steps higher than the nave. The Iconostasis does not sit directly on the edge of the sanctuary, but is usually set a few feet back from the edge of the top step. This forms a walkway in front of the iconostasis for the clergy, called a soleas. In the very center of the soleas is an extension (or thrust), often rounded, called the ambon, on which the deacon will stand to give litanies during the services.
The iconostasis, though often tall, rarely touches the ceiling. Acoustically, this permits the ekphoneses (liturgical exclamations) of the clergy to be heard clearly by the faithful. In small, modern churches the iconostasis may be completely absent: in such cases it is replaced by a few small icons on analogia (lecterns), forming a virtual divide.
The iconostasis typically has three openings or sets of doors: the Beautiful Gates or Holy Doors in the center, and the North and South Doors to either side. The Beautiful Gates are sometimes called the Royal Doors, but that name more properly belongs to the central doors connecting the narthex, or porch, to the nave. They remain shut whenever a service is not being held. Modern custom as to when they should be opened during services varies depending upon jurisdiction and local custom.
The North and South Doors are often called Deacons' Doors because the deacons use them frequently. Icons of sainted deacons are often depicted on these doors (particularly St. Stephen the Protomartyr and St. Ephrem the Syrian). Alternatively, they may be called Angels' Doors, and the Archangels Michael and Gabriel are often depicted there. The South Door is typically the "entrance" door, and Michael is depicted there because he is the "Defender"; the North Door is the "exit", and Gabriel is depicted here because he is the "Messenger" of God. These doors may also be casually referred to as the "side doors".
There are some exceptions where both the side doors depict Archangel Michael. The most notable exception is of the church of Saint George (Aghios Georgios) inside the Ecumenical Patriarchate of Constantinople (in today's Istanbul).
In many monastery churches and chapels (though often not in the Katholikon, the monastery's main church) one may find iconostases with only two doors: the Holy Doors and the North Door. These churches are used for simpler monastic observances when only a hieromonk would be serving alone. Since the priest seldom uses the South Door when he is serving the Divine Liturgy, the chapel can be made smaller by omitting that door.
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