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| A 'typical' post-Tridentine liturgical ordering (minus the altar rail) as seen in San Ignazio, Rome. |
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| The altar of San Ignazio in Rome -- unobscured and unobstructed. The altar is set apart from the rest of the presbytery by its own predella/steps, while the sanctuary in turn is set apart from the nave by its own elevation and typically also an altar rail. |
In the Christian East, of course, set on its own path since the Great Schism of 1054 and not encumbered by the same concerns with the Protestant Reformation as their Western European counterparts, the screen continued to reign supreme throughout this time and intensified and solidified itself further into the form we now know as the iconostasis -- which effectively amounts to a wall of icons with doors. In this particular manifestation, the altar and presbytery are barely visible at all.
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| The Byzantine iconostasis in its current form |
Naturally due to the shifting trajectories that happened between the particular churches of the East and West, particularly from the time of the Council of Trent onward, many Catholics (and perhaps Orthodox as well) tend to now consider these liturgical screens as somehow specifically "Eastern Christian" in character, but this isn't in fact the case at least historically speaking. It certainly is the case that, as the centuries passed and developments took place, these screens would find divergent expressions, but it must be noted that the same may also be said even of the screens found within the Latin church itself (for the liturgical screens of the churches of the Mediterranean region were frequently rather different in their character and arrangement than those of the European north). In point of fact, these balustrades are attested to in the churches from the very earliest centuries. For example, in a third century sermon by Eusebius, he describes the sanctuary of the basilica built during the time of Constantine in Tyre whose altar and presbytery was surrounded by a balustrade which included the ornamental latticework. The balustrades of this period were probably waist or chest high in height.
In terms of their origins, some speculate that such screens were possibly inherited from the Temple or the Synagogue, or also possibly from late antique Roman public buildings (where it was common, for example, to have such barriers separating the populace from the magistrates, orators, the Emperor or other dignitaries). A depiction of just that can be found in the reliefs found on the Arch of Constantine for example:
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| Detail, Arch of Constantine |
In terms of the particular variations and developments that might be found in liturgical screens within the Latin West, as noted we do see different approaches and iterations. In the region of Italy for example, a common approach sees a screen in the form of a balustrade or "cancelli" made of stone and characterized by latticework (from which the name "cancelli" is derived in point of fact). These were frequently taken in the form of a low wall upon which columns might or might not be attached and a horizontal beam on top. These are thought to have also been accompanied by veils akin to the curtains which were historically found in relation to the ciborium magnum. A good example of this type of screen can be seen still today in the basilica of S. Maria in Cosmedin in Rome (minus the curtains and minus the latticework):
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| S. Maria in Cosmedin, Rome |
In this particular example we see the balustrade separating the presbytery from the schola cantorum -- which itself is separated from the nave by yet another balustrade in this lower profile While this particular balustrade remains relatively open as it stands now, in other instances it would have been accompanied either by latticework or curtains as we have just noted.
Another variation on this type of arrangement can be seen in the late fourteenth century screen found in the Italo-Byzantine Basilica of St. Mark's in Venice.
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| Screen of San Marco, Venice |
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| Screen/Iconostasis of Panagia Ekatontapiliani, Greece |
As noted, however, in the Latin church we can likewise find developments and variations in the form of the screen, as for example in the instance of what has come to be referred to as the chancel or rood screen -- a form popular in England and the Low Countries (i.e. the north of Europe). In these instances we see that, unlike its southern counterparts -- which saw the schola cantorum pushed out in front of the screen with its own protruding cancelli -- the screen in these instances sits in front of both the choir/chancel as well as the presbyterium -- the choir now being manifest in pews arranged perpendicular to the altar itself. In terms of these screens, they were most frequently constructed of wood, though in larger churches (e.g. monasteries or cathedrals) also of stone. These screens were also frequently surmounted by a cross which during the medieval period was subject to great devotion including the lighting of "rood lights" before the cross.
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| The chancel screen of Crowland Abbey, Lincolnshire. As you shall see, the screen separates the nave from first the chancel, then the altar. |
What remains true here, however, is that while these various liturgical screens have their own particular nuances, they ultimately have much more that unites them than separates them.
Naturally one might ask what was their function or meaning. Some attribute symbolic associations to these screens, such as demarcating the Holy of Holies (as in the Temple of Jerusalem), or perhaps being influenced by the Torah shrines of late antique synagogues, but many surmise that these sorts of symbolic associations were more likely assigned after the fact as opposed to being their initial point of origin (which isn't to say such symbolic meanings aren't still meaningful). As is so often the case, many surmise there was likely a much more practical origin to them, namely that they served the practical purpose of keeping the throngs of the faithful separated from the clergy so that they would not disrupt the orderly and solemn execution of the liturgical rites (just as they seemed to similarly function in ancient Rome). That said, even in Roman times we see evidence that such balustrades were used to denote sacred spaces from secular one's, which at least lends at least some further credence to the idea that they may have also been consciously intended to also delineate the most sacred space within the church building as well.
