Hesychasm

Hesychasm (Greek: ἡσυχασμός, hesychasmos, from ἡσυχία, hesychia, "stillness, rest, quiet, silence") is an eremitic tradition of prayer in the Eastern Orthodox Church, and some other Eastern Catholic Churches, such as the Byzantine Rite, practised (Gk: ἡσυχάζω, hesychazo: "to keep stillness") by the Hesychast (Gr. Ἡσυχαστής, hesychastes).

Based on Christ's injunction in the Gospel of Matthew to "go into your closet to pray", hesychasm in tradition has been the process of retiring inward by ceasing to register the senses, in order to achieve an experiential knowledge of God (theoria).

The origin of the term hesychasmos, and of the related terms hesychastes, hesychia and hesychazo, is not entirely certain. According to the entries in Lampe's A Patristic Greek Lexicon, the basic terms hesychia and hesychazo appear as early as the 4th Century in such Fathers as St John Chrysostom and the Cappadocians. The terms also appear in the same period in Evagrius Pontikos (c. 345–399), who although he is writing in Egypt is out of the circle of the Cappadocians, and in the Sayings of the Desert Fathers.

The term Hesychast is used sparingly in Christian ascetical writings emanating from Egypt from the 4th century on, although the writings of Evagrius and the Sayings of the Desert Fathers do attest to it. In Egypt, the terms more often used are anchoretism (Gr. ἀναχώρησις, "withdrawal, retreat"), and anchorite (Gr. ἀναχωρητής, "one who withdraws or retreats, i.e. a hermit").

The term Hesychast was used in the 6th century in Palestine in the Lives of Cyril of Scythopolis, many of which lives treat of Hesychasts who were contemporaries of Cyril. Here, it should be noted that several of the saints about whom Cyril was writing, especially Euthymios and Savas, were in fact from Cappadocia. The laws (novellae) of the Emperor Justinian I (r. 527–565) treat Hesychast and anchorite as synonyms, making them interchangeable terms.

The terms hesychia and Hesychast are used quite systematically in the Ladder of Divine Ascent of St John of Sinai (523–603) and in Pros Theodoulon by St Hesychios (c. 750?), who is ordinarily also considered to be of the School of Sinai. It is not known where either St John of Sinai or St Hesychios were born, nor where they received their monastic formation.

It appears that the particularity of the term Hesychast has to do with the integration of the continual repetition of the Jesus Prayer into the practices of mental ascesis already used by hermits in Egypt. Hesychasm itself is not recorded in Lampe, which indicates that it is a later usage.

By the 14th century however, on Mount Athos the terms Hesychasm and Hesychast refer to the practice and to the practitioner of a method of mental ascesis that involves the use of the Jesus Prayer assisted by certain psychophysical techniques. Most likely, the rise of the term Hesychasm reflects the coming to the fore of this practice as something concrete and specific that can be discussed.

Books used by the Hesychast include the Philokalia, a collection of texts on prayer and solitary mental ascesis written from the 4th to the 15th Centuries, this collection existing in a number of independent redactions; the Ladder of Divine Ascent; the collected works of St Symeon the New Theologian (949–1022); and the works of St Isaac the Syrian (7th C.?–8th C.?), as they were selected and translated into Greek at the Monastery of St Savas near Jerusalem about the 10th century.

Hesychastic practice bears some formal resemblance to mystical prayer or meditation in Eastern religions (Buddhism, Hinduism, Jainism and Sufism, compare with yoga), although this similarity is often over-emphasized in popular accounts and rejected by actual Orthodox practitioners of Hesychasm. The practice may involve specific body postures and be accompanied by very deliberate breathing patterns. However, these bodily postures and breathing patterns are treated as secondary both by modern Athonite practitioners of Hesychasm and by the more ancient texts in the Philokalia, the emphasis being on the primary role of the uncreated Energies of God.

Hesychasts are fully integrated into the liturgical and sacramental life of the Orthodox Church, including the daily cycle of liturgical prayer of the Divine Office and the Divine Liturgy. However, Hesychasts who are living as hermits might have a very rare attendance at the Divine Liturgy and might not recite the Divine Office except by means of the Jesus Prayer. In general, the Hesychast restricts his external activities for the sake of his Hesychastic practice.

Hesychastic practice involves acquiring an inner stillness and ignoring the physical senses. In this, hesychasm shows its roots in Evagrius Pontikos and even in the Greek tradition of asceticism going back to Plato. The Hesychast interprets Christ's injunction in the Gospel of Matthew to "go into your closet to pray" to mean that one should ignore the senses and withdraw inward. Saint John of Sinai writes: "Hesychasm is the enclosing of the bodiless primary Cognitive faculty of the soul (Orthodoxy teaches of two cognitive faculties, the nous and logos) in the bodily house of the body." (Ladder, Step 27, 5, (Step 27, 6 in the Holy Transfiguration edition).)
In Step 27, 21 of the Ladder (Step 27, 22–3 of the Holy Transfiguration edition), St John of Sinai describes Hesychast practice as follows:

Take up your seat on a high place and watch, if only you know how, and then you will see in what manner, when, whence, how many and what kind of thieves come to enter and steal your clusters of grapes. When the watchman grows weary, he stands up and prays; and then he sits down again and courageously takes up his former task.

In this passage, St John of Sinai says that the primary task of the Hesychast is to engage in mental ascesis. This mental ascesis is the rejection of tempting thoughts (the "thieves") that come to the Hesychast as he watches in sober attention in his hermitage. Much of the literature of Hesychasm is occupied with the psychological analysis of such tempting thoughts (e.g. St Mark the Ascetic). This psychological analysis owes much to the ascetical works of Evagrius Pontikos, with its doctrine of the eight passions.

St. John Cassian is not represented in the Philokalia except by two brief extracts, but this is most likely due to his having written in Latin. His works (Coenobitical Institutions and the Conferences) represent a transmittal of Evagrius Pontikos' ascetical doctrines to the West. These works formed the basis of much of the spirituality of the Order of St Benedict and its offshoots. Hence, the tradition of St John Cassian in the West concerning the spiritual practice of the hermit can be considered to be a tradition parallel to that of Hesychasm in the Orthodox Church.

The highest goal of the Hesychast is the experiential knowledge of God. In the 14th Century, the possibility of this experiential knowledge of God was challenged by a Calabrian monk, Barlaam, who although he was formally a member of the Orthodox Church had been trained in Western Scholastic theology. Barlaam asserted that our knowledge of God can only be propositional. The practice of the Hesychasts was defended by St. Gregory Palamas.

In solitude and retirement the Hesychast repeats the Jesus Prayer, "Lord Jesus Christ, son of God, have mercy on me, a sinner." The Hesychast prays the Jesus Prayer 'with the heart'—with meaning, with intent, 'for real' (ontic). He never treats the Jesus Prayer as a string of syllables whose 'surface' or overt verbal meaning is secondary or unimportant. He considers bare repetition of the Jesus Prayer as a mere string of syllables, perhaps with a 'mystical' inner meaning beyond the overt verbal meaning, to be worthless or even dangerous. This emphasis on the actual, real invocation of Jesus Christ marks a divergence from Eastern forms of meditation.

There is a very great emphasis on humility in the practice of the Jesus Prayer, great cautions being given in the texts about the disaster that will befall the would-be Hesychast if he proceeds in pride, arrogance or conceit. It is also assumed in the Hesychast texts that the Hesychast is a member of the Orthodox Church in good standing.

While he maintains his practice of the Jesus Prayer, which becomes automatic and continues twenty-four hours a day, seven days a week, the Hesychast cultivates watchful attention (Gr. nepsis). Sobriety contributes to this mental askesis described above that rejects tempting thoughts; it puts a great emphasis on focus and attention. The Hesychast is to pay extreme attention to the consciousness of his inner world and to the words of the Jesus Prayer, not letting his mind wander in any way at all.

The Hesychast is to attach Eros (Gr. eros), that is, "yearning", to his practice of sobriety so as to overcome the temptation to acedia (sloth). He is also to use an extremely directed and controlled anger against the tempting thoughts, although to obliterate them entirely he is to invoke Jesus Christ via the Jesus Prayer.

The Hesychast is to bring his mind (Gr. nous) into his heart so as to practise both the Jesus Prayer and sobriety with his mind in his heart. The descent of the mind into the heart is taken quite literally by the practitioners of Hesychasm and is not at all considered to be a metaphorical expression. Some of the psychophysical techniques described in the texts are to assist the descent of the mind into the heart at those times that only with difficulty it descends on its own.

The goal at this stage is a practice of the Jesus Prayer with the mind in the heart, which practice is free of images (Pros Theodoulon). What this means is that by the exercise of sobriety (the mental ascesis against tempting thoughts), the Hesychast arrives at a continual practice of the Jesus Prayer with his mind in his heart and where his consciousness is no longer encumbered by the spontaneous inception of images: his mind has a certain stillness and emptiness that is punctuated only by the eternal repetition of the Jesus Prayer.

This stage is called the guard of the mind. This is a very advanced stage of ascetical and spiritual practice, and attempting to accomplish this prematurely, especially with psychophysical techniques, can cause very serious spiritual and emotional harm to the would-be Hesychast. St Theophan the Recluse once remarked that bodily postures and breathing techniques were virtually forbidden in his youth, since, instead of gaining the Spirit of God, people succeeded only "in ruining their lungs."

The guard of the mind is the practical goal of the Hesychast. It is the condition in which he remains as a matter of course throughout his day, every day until he dies. It is from the guard of the mind that he is raised to contemplation by the Grace of God.

The Hesychast usually experiences the contemplation of God as light, the Uncreated Light of the theology of St Gregory Palamas. The Hesychast, when he has by the mercy of God been granted such an experience, does not remain in that experience for a very long time, but he returns 'to earth' and continues to practise the guard of the mind.

The Uncreated Light that the Hesychast experiences is identified with the Holy Spirit. Experiences of the Uncreated Light are allied to the 'acquisition of the Holy Spirit'. Notable accounts of encounters with the Holy Spirit in this fashion are found in St Symeon the New Theologian's account of the illumination of 'George' (considered a pseudonym of St Symeon himself); in the 'conversation with Motovilov' in the Life of St Seraphim of Sarov (1759 – 1833); and, more recently, in the reminiscences of Elder Porphyrios (Wounded by Love pp. 27 – 31).

Orthodox Tradition warns against seeking ecstasy as an end in itself. Hesychasm is a traditional complex of ascetical practices embedded in the doctrine and practice of the Orthodox Church and intended to purify the member of the Orthodox Church and to make him ready for an encounter with God that comes to him when and if God wants, through God's Grace. The goal is to acquire, through purification and Grace, the Holy Spirit and salvation. Any ecstatic states or other unusual phenomena which may occur in the course of Hesychast practice are considered secondary and unimportant, even quite dangerous. Moreover, seeking after unusual 'spiritual' experiences can itself cause great harm, ruining the soul and the mind of the seeker. Such a seeking after 'spiritual' experiences can lead to spiritual delusion (Ru. prelest, Gr. plani)—the antonym of sobriety—in which a person believes himself or herself to be a saint, has hallucinations in which he or she 'sees' angels, Christ, etc. This state of spiritual delusion is in a superficial, egotistical way pleasurable, but can lead to madness and suicide, and, according to the Hesychast fathers, makes salvation impossible.

Mount Athos is a centre of the practice of Hesychasm. St Paisius Velichkovsky and his disciples made the practice known in Russia and Romania, although Hesychasm was already previously known in Russia, as is attested by St Seraphim of Sarov's independent practice of it.

About the year 1337, hesychasm attracted the attention of a learned member of the Orthodox Church, Barlaam, a Calabrian monk who at that time held the office of abbot in the Monastery of St Saviour in Constantinople and who visited Mount Athos. Mount Athos was then at the height of its fame and influence, under the reign of Andronicus III Palaeologus and under the 'first-ship' of the Protos Symeon. On Mount Athos, Barlaam encountered Hesychasts and heard descriptions of their practices, also reading the writings of the teacher in Hesychasm of St Gregory Palamas, himself an Athonite monk. Trained in Western Scholastic theology, Barlaam was scandalized by hesychasm and began to combat it both orally and in his writings. As a private teacher of theology in the Western Scholastic mode, Barlaam propounded a more intellectual and propositional approach to the knowledge of God than the Hesychasts taught.

Barlaam took exception to the doctrine entertained by the Hesychasts as to the nature of the light, the experience of which was said to be the goal of Hesychast practice, regarding it as heretical and blasphemous. It was maintained by the Hesychasts to be of divine origin and to be identical to the light which had been manifested to Jesus' disciples on Mount Tabor at the Transfiguration. This Barlaam held to be polytheistic, inasmuch as it postulated two eternal substances, a visible and an invisible God.

On the Hesychast side, the controversy was taken up by St Gregory Palamas, afterwards Archbishop of Thessalonica, who was asked by his fellow monks on Mt Athos to defend hesychasm from the attacks of Barlaam. St Gregory himself was well-educated in Greek philosophy. St Gregory defended hesychasm in the 1340s at three different synods in Constantinople, and he also wrote a number of works in its defense.
In these works, St Gregory Palamas uses a distinction, already found in the 4th century in the works of the Cappadocian Fathers, between the energies or operations (Gr. energeies) of God and the essence of God. St Gregory taught that the energies or operations of God were uncreated. He taught that the essence of God can never be known by his creature even in the next life, but that his uncreated energies or operations can be known both in this life and in the next, and convey to the Hesychast in this life and to the righteous in the next life a true spiritual knowledge of God. In Palamite theology, it is the uncreated energies of God that illumine the Hesychast who has been vouchsafed an experience of the Uncreated Light.

In 1341 the dispute came before a synod held at Constantinople and presided over by the Emperor Andronicus III; the synod, taking into account the regard in which the writings of the pseudo-Dionysius were held, condemned Barlaam, who recanted and returned to Calabria, afterwards becoming bishop in the Roman Catholic Church.

One of Barlaam's friends, Gregory Akindynos, who originally was also a friend of St Gregory Palamas, took up the controversy, which also played a role in the civil war between the supporters of John Cantacuzenus and John V Palaeologus. Three other synods on the subject were held, at the second of which the followers of Barlaam gained a brief victory. But in 1351 at a synod under the presidency of the Emperor John VI Cantacuzenus, Hesychast doctrine was established as the doctrine of the Orthodox Church.
The contemporary historians Cantacuzenus and Nicephorus Gregoras deal very copiously with this subject, taking the Hesychast and Barlaamite sides respectively.

Up to this day, the Latin Rite Catholic Church has never fully adopted hesychasm, especially the distinction between the energies or operations of God and the essence of God, and the notion that those energies or operations of God are uncreated. In the Catholic Encyclopedia of 1910, in which Adrian Fortescue charges Palamas with heresy and S. Vailhé characterizes Hesychasm as "no more than a crude form of auto-suggestion" and "monstrous errors" and calls the theology of Palamas a "resurrection of polytheism." As Thomas Aquinas in his work Summa Contra Gentiles dedicates an entire chapter to the concept. Aquinas' chapter is called That in God Existence and Essence is the same.

In Latin theology as it has developed since the Scholastic period, the essence of God can be known, but only in the next life; the grace of God is always created; and the essence of God is pure act (Actus and force as Actus et potentia), so that there can be no distinction between the energies or operations and the essence of God (see, e.g., the Summa Theologica of St. Thomas Aquinas). Some of these positions depend on Aristotelian metaphysics.

Catholic philosopher Michael Liccione argues that the Essence-Energies distinction is true and compatible with the Catholic dogma of absolute divine simplicity according to the definition given at the Fourth Council of the Lateran and the First Vatican Council.

This account from an acquaintance of the Anglican spiritual writer and scholar of Christian mysticism, Evelyn Underhill, 1875-1941, represents a Western and contemporary witness to such an experience of the Uncreated Light.

"It was in October 1937 that I met her first--invited to tea with her in her Campden Hill Square house. She had just had one of her bad illnesses. The door of the room into which I was shown was directly behind the big arm-chair in which she was sitting facing a glowing fire. As I entered she got up and turned around, looking so fragile as though 'a puff of wind might blow her away' might be literally true in her case, but light simply streamed from her face illuminated with a radiant smile. . . . One could not but feel consciously there and then (not on subsequent recognition or reflection) that one was in the presence of the extension of the Mystery of our Lord's Transfiguration in one of the members of His Mystical Body. I myself never saw it repeated on any later meeting though other have probably seen the same thing at other times. It told one not only of herself, but more of God and of the Mystical Body than all her work put together."

According to some of the adepts of the Jewish Merkabah mystical tradition, if one wished to "descend to the Merkabah" one had to adopt the prayer posture taken by the Prophet Elijah in I Kings 18:42, namely to pray with one's head between one's knees. This is the same prayer posture used by the Christian Hesychists and is the reason that they were mocked by their opponents as "navel gazers." This bodily position and the practice of rhythmically breathing while invoking a divine name seems to be common to both Jewish Merkabah mysticism and Christian Hesychasm. Thus the practice may have origins in the ascetical practices of the biblical prophets.

Alan Segal in his book Paul the Convert suggests that the Apostle Paul may have been an early adept of Merkabah mysticism in which case what was novel to Paul's experience of divine light on the road to Damascus was not the experience of divine light itself, but that the source of this divine light identified himself as the Jesus whose followers Paul was persecuting. Daniel Boyarin notes that Paul's own account of this experience would therefore be the earliest first person account of the mystical vision of a Merkabah adept.

Not Made by Hands: Acheiropoieta

Acheiropoieta (Byzantine Greek: αχειροποίητα, "not handmade"; singular acheiropoieton) — also called Icons Not Made by Hand (and variants) — are a particular kind of icon which are alleged to have come into existence miraculously, not created by a human painter. Invariably these are images of Jesus or the Virgin Mary. The most notable examples are, in the Eastern church the Image of Edessa or Mandylion, and in the West, the Veil of Veronica and the Shroud of Turin.

Such images functioned as powerful relics as well as icons, and their images were naturally seen as especially authoritative as to the true appearance of the subject. Like icons believed to be painted from the live subject, they therefore acted as important references for other images in the tradition. They therefore were copied on an enormous scale, and the belief that such images existed, and authenticated certain facial types, played an important role in the conservatism of the Byzantine tradition. Beside, and conflated with, the  legend of the Image of Edessa, was the tale of the Veil of Veronica, whose very name signifies "true icon" or "true image", the fear of a "false image" remaining strong.

Surviving examples of this genre bear a marked resemblance to each other and have contributed to the bearded image of Jesus generally recongnisable up to the present day. The respect accorded to these traditions remains much stronger in the Eastern Orthodox Church; many Latin Catholic images, such as the Virgin of Guadalupe, have accrued such traditions, but with the exception of the Shroud of Turin and some of the others discussed below, these are not encouraged by the Holy Roman Catholic Church.

Such icons were seen as powerful arguments against iconoclasm. In a document apparently produced in the circle of the Patriach of Constantinople, which purports to be the record of a Church council of 836, a list of acheiropoieta and icons miraculously protected is given as evidence for divine approval of icons. The acheiropoieta listed are:

1. The Image of Edessa, described as still at Edessa;
2. The image of the Virgin at Lydda in Israel, which was said to have miraculously appeared imprinted on a column of a church built by the apostles Peter and John;
3. Another image of the Virgin, three cubits high, at Lydda in Israel, which was said to have miraculously appeared in another church.

The nine other miracles listed deal with the maintenance rather than creation of icons, which resist or repair the attacks of assorted pagans, Arabs, Persians, scoffers, madmen, iconoclasts and Jews.

This list seems to have had a regional bias, as other than famous images are not mentioned, such as the Christ of Camuliana, later brought to the capital. Another example, which indisputably still exists, is a mosaic of the young Christ from the sixth century in the church of the Latomos monastery in Thessaloníki dedicated to Saint David. This was apparently covered by plaster during the Iconoclastic period, towards the end of which an earthquake caused the plaster to fall down, revealing the image (during the reign of Leo V, 813-20). However this was only a subsidiary miracle, according to the account we have. This says that the mosaic was being constructed secretly, during the 4th century persecution of Galerius, as an image of the Virgin, when it suddenly was transformed overnight into the present image of Christ.

According to Christian legend, the Image of Edessa, known to Orthodox Christians as the Mandylion, a Byzantine Greek word not applied in any other context, was a holy relic consisting of a square or rectangle of cloth upon which a miraculous image of the face of Jesus was imprinted — the first icon, which all others are based.

According to the legend, King Abgar of Edessa wrote to Jesus, asking him to come cure him of an illness. Abgar received an answering letter from Jesus, declining the invitation, but promising a future visit by one of his disciples. Along with the letter went a likeness of Jesus. This legend was first recorded in the early fourth century by Eusebius of Caesarea, who said that he had transcribed and translated the actual letter in the Syriac chancery documents of the king of Edessa. Instead, the apostle "Thaddaeus" is said to have come to Edessa, bearing the words of Jesus, by the virtues of which the king was miraculously healed.

Veronica's Veil, known in Italian as the Volto Santo or Holy Face (but not to be confused with the carved crucifix Volto Santo of Lucca) is a legendary religious relic. Some people believe that Veronica from Jerusalem encountered Jesus along the Via Dolorosa on the way to Calvary. When she paused to wipe the sweat (Latin suda) off his face with her veil, his image was imprinted on the cloth. The event is commemorated by one of the Stations of the Cross. According to legend, Veronica later traveled to Rome to present the cloth to the Roman Emperor Tiberius. Legend has it that it has miraculous properties, being able to quench thirst, restore sight, and sometimes even raise the dead.

After being for centuries the most revered and copied Catholic image of Christ, in recent times it has rather been overshadowed by the Shroud of Turin.

The Shroud of Turin (or Turin Shroud) is a linen cloth bearing the hidden image of a man who appears to have been physically traumatized in a manner consistent with crucifixion. The image is most clearly visible as a photographic negative, as was first observed in 1898 on the reverse photographic plate when amateur photographer Secondo Pia was unexpectedly allowed to photograph it. The shroud is kept in the royal chapel of the Cathedral of Saint John the Baptist in Turin, Italy. The Roman Catholic Church has approved this image in association with the devotion to the Holy Face of Jesus and some believe it is the cloth that covered Jesus at burial.

The Lateran Palace Image, also called the Uronica, is kept in what was once the pope’s private chapel, in a room now known as the Sancta Sanctorum ("Holy of Holies") at the top of the Scala Sancta ("Holy Stairs") in a surviving part of the old Lateran Palace in Rome. The legend is that this icon was begun by St Luke and finished by angels.

It is thought that the icon was over-painted in Rome between the 5th and 6th century. Today only slight traces under overpainting remain of the original image of an enthroned Christ with a crossed halo, in the classic pose of the Teacher holding the roll of the law in His left hand with His right raised in benediction. Many times restored, the face completely changed when Pope Alexander III (1159-1181) had the present one, painted on silk, placed over the original. Innocent III (1189-1216) covered the rest of the holy icon with embossed silver, but other later embellishments have by now completely disguised its surface. It has also been cleaned during the recent restoration. The doors protecting the icon, again in embossed silver, are of the 15th century. It has a baldachin in metal and gilded wood over it, replacing the one by Caradaossi (1452-1527), lost during the sack of Rome in 1527. The image itself was last inspected by the Jesuit art historian J. Wilpert in 1907.

As early as the reign of Pope Sergius I (687–701) there are records of the image being carried in annual procession at certain feasts, and Stephen II (752–757) carried the image on his shoulders in a procession to counter a threat from the Lombards. By the ninth century its elaborate procession had become a focus of the Feast of the Assumption. In the Middle Ages the Pope and the seven cardinal-bishops would celebrate masses in the small sanctuary where it was housed, and at times would kiss its feet. Although no longer a specific liturgical object, some Romans still venerate this icon, considering it a last hope in disasters and memorable events in the capital, a veneration which can be compared with that for the other ancient icon of the Madonna “Salus Populi Romani” in St. Mary Major, again in Rome. The former icon used to be taken across Rome annually in procession to "meet" the latter on the Feast of the Assumption.

Iconostasis, Templon, Rood Screen, Pulpitum

In Eastern Christianity an iconostasis (plural: iconostases) is a wall of icons and religious paintings, separating the nave from the sanctuary in a church. The word comes from the Greek εἰκονοστάσι(-ον) (eikonostási(-on), still in common use in Greece and Cyprus), which means "icon stand". Icon stand also refers to a portable icon stand that can be placed anywhere within a church. The iconostasis evolved from the Byzantine templon, a process complete by the fifteenth century.

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.

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. In some places they are nearly always open and are closed only at specific times; in others they are nearly always shut and are opened only at specific times.

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.

In many monastery churches and chapels (though often not in the catholicon, 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.

A number of guidelines or rubrics govern which icons are on which parts of the iconostasis, although there is some room for variation. In its fullest Slavic development it comprised five tiers of icons:

The bottom tier is sometimes called Sovereign. On the right side of the Beautiful Gates (from the nave facing forward) is an icon of Christ (often Pantokrator), which symbolizes his Second Coming and on the left side is an icon of the Theotokos (Virgin Mary), symbolizing Christ's incarnation, and entrance into this world. Therefore, all things take place between Christ's first and second coming. Other icons on this tier beside those on the doors themselves usually include depictions of the patron saint or feast day to which the church is dedicated, the patron saint of the nation (Greece is St. John the Baptist, Russia is St. Nicholas of Myra). Above this are two interchangeable tiers: the Deisis and the Twelve Great Feasts:

In the center of the Deisis is a large icon of Christ Enthroned. To the left and right are icons of John the Baptist and the Theotokos in attitudes of supplication. They are often flanked by icons of the Archangels Michael and Gabriel, then Sts. Peter and Paul, and then any other important Church Fathers that may be desired for inclusion as space allows.

The Feasts tier contains icons of the twelve Great Feasts of the liturgical year with the icon of the Mystical Supper in the middle. Above this, the top two tiers are also interchangeable with each other:

The Old Testament Prophets and Patriarchs—the latter including the twelve sons of Jacob—often to either side of an icon of Our Lady of the Sign; and the Twelve Apostles, often to either side of an icon depicting the Hospitality of Abraham and Sarah.

The Sovereign tier is always present, but all the others may be omitted. Preference is given to the Deisis or the Feasts tiers if only some of them can be included. Only the largest and most elaborate iconostases include all five.

There are rules regarding who may enter or leave the sanctuary, and by which door. Neither the Beautiful Gates nor the space between them and the altar may be used by laity under any circumstances, although infant boys are taken into the altar through them in the "churching" rite, or, if a girl, the infant is simply presented at the doors. Bishops may enter through the Beautiful Gates at any time; priests and deacons may do so only at specific times during the services when the Gates are open (but during Bright Week they always enter and exit through them). All others enter the sanctuary through the side doors.

In a convent only the abbess and elder nuns are permitted to enter the sanctuary, and only by the side doors. The abbess may enter at any time, but the other nuns need a blessing to enter.

Male members of the laity who are usually allowed to enter the sanctuary include those involved in the running of the particular church, i.e. cantors and choristers, altar servers, church keepers and vestrymen, etc. Entering the sanctuary for no good reason or without a blessing is forbidden even if no religious service is being held at the time.

These guidelines were developed over the course of many centuries, with both theologically symbolic and practical reasons for them.

The Iconostasis does not really "separate" the nave from the Holy of Holies; rather, it brings them together. The Iconostasis is the link between heaven (the Holy of Holies) and the nave (The Holy Place). Therefore everything is symbolic upon the Iconostasis. The Icons of Christ the Theotokos and various saints and feasts are there because Christ, the Theotokos, the saints etc., lead us and guide us into the Holy of Holies. Therefore the personages on the Icons upon the Iconostasis guide us into heaven, and therefore the Iconostasis connects not separates. The Icons upon the Iconostasis also are windows and bridges into heaven (although all icons, no matter where, are windows and bridges into heaven). Therefore, in a sense the Iconostasis represents Christ, who is the connection, the door, between both realms. The perfect explanation for the Iconostasis, and its uniting purpose, is seen in Hebrews 10:19-20, "Therefore, brethren, since we have confidence to enter the sanctuary by the blood of Jesus, by the new and living way which he opened for us through the curtain, that is through his flesh."

Archaeological evidence from the St. John of Stoudios monastery in Constantinople suggests that the Iconostasis evolved from the early templon. A basilica dedicated to John the Baptist was built in 463 AD. In it the chancel barrier surrounded the altar in a π shape, with one large door facing the nave and two smaller doors on the other sides. Twelve piers held chancel slabs of about 1.6 meters in length. The height of the slabs is not known. The chancel barrier was not merely a low parapet (a short wall); remains of colonnettes have been found, suggesting that the barrier carried an architrave on top of the columns.

The templon gradually replaced all other forms of chancel barriers in Byzantine churches in the 6th, 7th, and 8th centuries except in Cappadocia. Sacred tradition ascribes the invention of the solid iconostasis to Saint Basil the Great.

As late as the 10th century, a simple wooden chancel barrier separated the apse from the nave in the rock-cut churches in Derinkuyu, though by the late 11th century, the templon had become standard. This may have been because of the veneration and imitation of the Great Church Hagia Sophia in Constantinople, though the columnar form of chancel barrier does predate Hagia Sophia.

In recent years, especially in the diaspora, there has been a liturgical movement favouring a more open style of Iconostasis. These Iconostases may be only one or two tiers, with a wide opening for the royal doors.

The rood screens or pulpitums that most Roman Catholic large churches and cathedrals in many parts of Europe had acquired by late medieval times occupied a similar position between chancel and nave but had a different function. The choir was usually east of the screen. Many survive, often most completely in Scandinavia, and more were built in the Gothic Revival, particularly in Anglican churches in England. In examples in wood painted panels typically only went up to about waist height, with a section with wooden tracery above allowing a view through, and then a large carved beam supporting a rood cross crucifix, often life-size, above. Larger churches had stone screens, which might impede virtually all view by the congregation.

The Oriental Orthodox and Eastern Catholic churches which follow Oriental rites differ among themselves about the use of the iconostasis. The Armenian and Syriac churches often use a curtain, but not a solid iconostasis. The Coptic and Ethiopian churches use an iconostasis often made of latticework, so that it is semi-transparent.