Archbishop Hilarion Alfeyev weighs in (from the Online Orthodox Catechism):http://orthodoxeurope.org/page/12/1.aspx
The beauty of Orthodox services. The Sanctuary
One of the most noticeable qualities of the divine services is their beauty and splendour. This beauty is also reflected in the external arrangement of the church. There is a well-known story from the ancient “Chronicle of the Years” (Povest’ vremennykh let) that tells of how ambassadors of Prince Vladimir, sent by him to various countries to select the correct faith for Rus’, returned, struck by the service which they attended in Hagia Sophia in Constantinople: “We did not know if we were on heaven or earth, for there is no such splendour and beauty on earth, and we are at a loss how to express what we saw. We only know that God is with these people and that their services were better than those of all other countries”. Who knows what the future of Russia may have resembled if Prince Vladimir’s ambassadors did not visit Hagia Sophia and were not inspired by the grandeur of the church and the beauty of Orthodox services?
There is a deep symbolism and edifying quality in the very structure of the Orthodox churches. They are built either in the form of a cross or a rectangle (basilica), the latter symbolizing the Church as a ship, as Noah’s ark, in which the New Israel travels to the Heavenly Kingdom. Byzantine and Russian churches are decorated with frescoes which depict various events from Sacred History. Series of frescoes or mosaics stretch out along the inside of the church, explaining to the faithful the main themes of salvation history and serving as a “Bible in pictures”. Classical examples of this are the early 13th-century Byzantine mosaics in the Sicilian town of Monreale. Two rows of mosaics are visible in the main part of the town’s church: one depicts Old Testament history from the creation of the world to Israel’s entering the Promised Land, while the other New Testament representations from Christ’s Nativity to His Ascension. On the walls are portrayed the apostles Peter and Paul, as well as various events from the life of the early Church as described in the Acts of the Apostles. The centerpiece of this entire composition is comprised of icons of Christ and the Mother of God in the sanctuary’s apse.
Ancient churches had no iconostasis; only a low barrier that divided the sanctuary from the rest of the church so that the former remained “transparent”. The iconostasis appeared gradually: at first it was one-tiered, then later, multi-tiered, the latter becoming especially widespread in ancient Russia. Today the iconostasis is often seen as a wall between the sanctuary and the rest of the church, between the clergy and the faithful. In fact, however, it is a window into another world, for the hosts of saints gaze down at the faithful from the icons. The aim of the iconostasis is not to create an obstacle, but rather to bring the faithful into the mystical life of the “Triumphant Church”, whose saints and angels serve God in incessant rejoicing.
According to the current practice of the Russian Church, the “royal doors” remain open only during episcopal services or at other special occasions. When services are conducted by a priest, they are opened only from time to time. In Greek church practice the royal doors remain open during the entire Liturgy, and some churches in Greece do not have them at all, but only a curtain that is drawn shut after services. In this case the Greek practice corresponds better to the tradition of the early Church and the original meaning of the Liturgy. Just as with the reading of the “silent” prayers, the hiding of the clergy behind massive royal doors does not at all encourage a better understanding of the Liturgy by the faithful. On the contrary, it creates for them a sense of a lack of participation in what is happening in the sanctuary. The impression is that the Liturgy is viewed as something that takes place between the priest and God, in which the congregation plays no active role.
The sanctuary is often seen as a kind of closed, “off-limits” space, where clergy and acolytes can relax far from the eyes of the faithful. Such a view, of course, totally contradicts its significance as a place of the special presence of God. It is the abode of the Divine Shekhina, the same glory of God that once filled the Holy of Holies of the Jerusalem Temple. Everybody in the sanctuary should maintain a reverent silence, broken only by the reading of prayers or remarks necessary for the proper conduct of the services. Conversation about other matters in the sanctuary is inadmissible.
Nobody or nothing superfluous should be present in the sanctuary: no “guests of honour” and no unnecessary objects; only those people directly involved in the service and items necessary for its celebration. This sacred space must not be turned into a warehouse of liturgical vessels, a library, a sacristy or anything else. I have seen flagrant disorder in the sanctuaries of several Orthodox churches in the West, where books, commemoration lists, plates, cups for drinking after communion, half-burnt candles, coals for censers, matchboxes, rags and even rolls of toilet paper were strewn about. Once during the Liturgy I saw in the corner of my eye a fire burning at one end of the sanctuary. It turned out that the priests and acolytes were burning the commemoration lists that had been read. Such things occur when there is complete insensitivity to the sanctity of the church and its services.
A church decorated with icons and frescoes, a clean, orderly sanctuary and reverent behaviour by the clergy are all pre-requisites if the Orthodox divine services are to be a school of theology.