What is an altar?
An altar is a raised structure or table in a church, chapel or temple that serves as the focal point for religious rituals, particularly the celebration of the Eucharist (communion). In church architecture, the altar is typically positioned at the east end of the building, within or near the chancel or choir area.
History and origins
The word “altar” comes from the Latin altare, meaning “high place.” Altars have been used in religious practice for thousands of years:
- Ancient altars were often stone platforms used for offerings and sacrifices
- Early Christian altars were simple wooden tables, sometimes placed over the tombs of martyrs
- Medieval altars became elaborate stone structures, often richly decorated with carvings, gold leaf and reliquaries
- Post-Reformation altars in Protestant churches returned to simpler wooden communion tables
Types of altars
| Type | Description | Common in |
|---|---|---|
| Fixed altar | Permanently installed stone or masonry table, consecrated in place | Roman Catholic, Orthodox churches |
| Portable altar | A smaller, movable altar stone or slab | Chapels, temporary worship spaces |
| High altar | The main altar in a church, positioned in the sanctuary | Cathedrals, large churches |
| Side altar | A secondary altar in a side chapel or aisle | Catholic churches, cathedrals |
| Communion table | A simpler wooden table used for the Lord’s Supper | Protestant, Reformed churches |
Construction and materials
Traditional altars are built from:
- Natural stone — granite, marble or limestone, often as a single slab (mensa) on supports
- Brick or masonry — a solid block structure, rendered and painted or clad in stone
- Wood — especially in Protestant churches, often oak or another hardwood
- Metal or concrete — in modern church architecture, sometimes combined with glass or stone
A traditional stone altar typically consists of:
- Mensa — the flat top surface, at least large enough to hold the liturgical vessels
- Stipes — the supporting base, which can be a solid block, columns or a pedestal
- Altar stone — a consecrated slab containing relics, embedded in or placed on the mensa
Dimensions
There are no universal standard dimensions, but common guidelines include:
- Height: approximately 90-100 cm (similar to a standard table)
- Depth: at least 60 cm
- Width: 150-250 cm depending on the size of the church
Related terms
- Altar rail
- Ambo
- Ambulatory
- Chancel
- Nave
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