Altar rails

The altar rail or communion rail is a low barrier, sometimes ornate and usually of made of stone, wood or metal in some combination, delimiting the chancel or the sanctuary and altar in a church from the nave and other parts that contain the congregation. Often a gate, or just a gap, at the centre divides the line into two parts. Rails are a very common, but not inevitable, feature of Roman Catholic, Anglican, Lutheran, and Methodist churches. Catholic usage prefers "Communion rail". They are usually about two feet 6 inches high, with a padded step at the bottom, and designed so that the wider top of the rail can support the forearms or elbows of a kneeling person.

The altar rail is a modest substitute for earlier barriers demarcating the chancel, the area containing the altar, which was reserved (with greatly varying degrees of strictness) for officiating clergy (including boys as choristers and altar servers). Although it only emerged after the Protestant Reformation, it has been found convenient by both Catholic and more traditional Anglican and Protestant churches, although it is disliked by many Reformed and Evangelical churches.

Barriers of various kinds often mark off as especially sacred the area of a church close to the altar, which is largely reserved for ordained clergy. The templon was typical for the Late Antique period. In the Armenian Apostolic Church, curtains are still drawn to cut off that area during the holiest moments of the liturgy. In Eastern Orthodox and related rites, this evolved into a solid, icon-clad screen, called the iconostasis, that has three doorways which usually have doors and curtains that can be closed or drawn aside at various times.

Following the exposition of the doctrine of transubstantiation at the fourth Lateran Council of 1215, clergy were required to ensure that the blessed sacrament was to be kept protected from irreverent access or abuse; and accordingly the area of the church used by the lay congregation was to be screened off from that used by the clergy. Apart from the congregation, pet dogs were often taken to church, and a dog-proof barrier was needed (more recent rails often fail in this). Barriers demarcating the chancel, such as the rood screen, became increasing elaborate, but were largely swept away after both the Protestant Reformation and then the Counter-Reformation prioritized the congregation having a good view of what was happening in the chancel. Now the low communion rail is generally the only barrier; despite being essentially a Counter-Reformation invention, this has proved useful and accepted in the Protestant churches that dispense communion. However the screen enjoyed a small revival in the 19th century, after the passionate urgings of Augustus Pugin, who wrote A Treatise on Chancel Screens and Rood Lofts, and others.

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