Previously in this series, we touched upon the Paleochristian and Early Medieval forms of the altar. In this next instalment we shall treat of the later medieval forms that developed from this arrangement. As we noted in the previous article, the earliest form of the altar came in a freestanding form covered with the ciborium magnum -- a stationary, architectural canopy set on four columns. In their earliest incarnations, the altars of that particular period were smaller than those we are accustomed to today and the ornaments (such as lamps, candlesticks and cross) were typically either suspended from the great ciborium or, in the case of candlesticks, put around it on the floor in the form of great standards or on wall brackets, as hanging coronae, etc.. They were not placed upon the altar itself.
By the eighth to ninth century, however, we enter the great age of the relics -- and of course, this also corresponds to the timeframe when the Roman martyrs relics where being brought out of the catacombs and into the city and its churches proper. These relics began to be allowed on the altars as well as behind them and above them in various sorts of relic shrines. As a result, the shape of the altar began to expand in order to accommodate these arrangements. Related to this, on great feasts sometimes moveable decorations, be it a painting, a textile, or a decorative piece of metalwork, would be placed behind the high altar to add additional solemnity and festivity to the occasion.
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| An example of an ornamental work placed behind the altar and ciborium as still seen today in San Marco in Venice |
By the end of the middle ages (a subject for our next article) this would develop into the retablo and/or reredos, which would either come to be affixed to the altar itself or to the wall behind.
As the relics started to shift from being reserved in the confessio beneath the altar to instead being found on or around the altar itself, the confessio would come to fade from prominence. Similarly, with the growth in the size of the altars, as well as the advent of relic shrines in and behind the altar, the ciborium magnum itself would start to fade but for places like Rome. This likewise influenced the particular form of the altar, for while earlier altars could either come in "table" form or "tomb" form (denoted as such because they derive from the box-like shape of the sarcophagus of a martyrs tomb upon which Mass might be offered), the ever increasing size of the altars of this period made the tomb form the best and most practical choice to support the weight of this evolved altar arrangement.
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| Above: A historical altar in "table" form. Below: The "tomb" form of altar. |
Concurrent to their ever increasing size, altars also began to be placed back further within the sanctuaries; this not only contributed to the gradual disappearance of the ciborium magnum, but also the advent of elements that were intended to compensate for that loss such as the "tester" (a hanging canopy that was suspended from the ceiling). What's more, what had been the four columns of the ciborium magnum would become, in some places, riddel posts on or near the four corners of the altar. From these were suspended riddel curtains and it is speculated that these curtains were themselves possibly derived from the curtains that once hung from the ciborium magnum (called tetravela). In places such as Italy, the ciborium proper with its curtains persisted into the thirteenth century, while this other form (often erroneously denoted as the "English altar") came to be more common in places such as England and northern Europe more generally.
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| The Evolution of the Altar: An illustration, adapted from Anson, showing the evolution from a ciborium with its four supporting columns, canopy and curtains, to an altar with four riddel posts, curtains and a suspended canopy. |
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| A modern approximation of this type and period of altar by Sir Ninian Comper |
By about the eleventh century, candlesticks would come to be placed on the altar itself (at first only during the liturgy proper, but eventually they would become permanent fixtures on it as we are familiar today) and eventually an altar cross would come to join these (for prior to this the cross was either suspended from the ciborium or was otherwise simply near the altar, whether the processional cross or otherwise).
There was no tabernacle placed on the altar at this point of history, the Sacrament generally being reserved elsewhere such as an aumbry in the wall of the church, a sacrament tower, or, from about the eleventh century, in a hanging pyx that was generally covered with a veil. Which method was used varied by region and some suggest that tabernacles only began to be placed upon the altar proper from about the thirteenth century onward, but this was by no means the universal practice at that point.
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| An example of a Sacrament Tower (left) and veiled hanging pyx (right) |
Neither were the number of candles and candlesticks found on the altar universal in practice at this point in its history for it too varied by particular place and custom. One sees records of various numbers, including five, seven and nine, but in most medieval illuminations one will see two used, one placed to either side of the altar.
Finally, in concluding our considerations of the form of the altar during this period of history, it is worth noting that the use of the predella, which was common from about the fourth century onward, was maintained during this period, most frequently in the form of a single step/platform -- something which, by about the fifteenth century onward, would more commonly become three).
