Whether located in their own chapels, on altars or otherwise, these tabernacles can come in various shapes and sizes, ranging from tabernacles that are embedded into the gradines of an altar, thus primarily appearing either as a door (akin to the way an aumbry would similarly appear within the context of a wall), or as a rectangular structure set within the gradines. In other instances, the tabernacle may be somewhat cylindrical in shape, as for example that which seen here at the beautiful Roman church of S. Salvatore in Lauro:
Tabernacles, of course, may come in other variations on these two basic shapes, but most break down to some variation on them.
In our own day, many churches leave their tabernacles -- often like the altar itself sadly -- unveiled, but according to the Roman tradition, any tabernacle containing the reserved Blessed Sacrament is to be veiled -- and by this what is meant is not simply the interior veil that many tabernacles have, but the exterior veil (conopaeum). As in the case of altars, some will point to the particular beauty of a tabernacle -- perhaps made with carvings or of precious metals -- as a reason for keeping the tabernacle without an exterior veil, but here again the tradition of the Church says otherwise, and many purists will argue that even the form of veil that manifests simply as a tabernacle door cover is not sufficient -- or at least not in full accord with the Roman tradition which envisions a sort of tent or canopy that envelops the entirety of the tabernacle.
Perhaps one of the very best and most impressive examples in Rome of just such a tabernacle veil is at the aforementioned church of San Salvatore in Lauro. Now you saw their tabernacle above in its unveiled form, but for most of the liturgical year, the tabernacle here is veiled in a textile of the liturgical colour of the season or Mass of the day and I believe our readers will see for themselves the powerful impact such veils can have (just as they do for the altar in the form of the antependium). I think our readers will agree that, when done properly, the case for the tradition of fully veiled tabernacles makes itself.
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