And thou shalt command the children of Israel, that they bring thee pure oil olive beaten for the light, to cause the lamp to burn always. In the tabernacle of the congregation without the veil, which is before the testimony, Aaron and his sons shall order it from evening to morning before the LORD: it shall be a statute for ever unto their generations on the behalf of the children of Israel. (KJV)|
In Judaism, the sanctuary lamp is known by its Hebrew name, ner tamid (נר תמיד), which is usually translated as "eternal flame" or "eternal light." Hanging or standing in front of the ark in every Jewish synagogue, it is meant to represent the menorah of the Temple in Jerusalem as well as the continuously burning fire on the altar of burnt offerings in front of the Temple. It also symbolizes God's eternal presence, and is therefore never extinguished. They are also intended to draw parallels between God and fire, or light, which is emphasized throughout the book of Exodus in the Torah.
In a Reform-Jewish congregation, it is often used to symbolize the light released from the shards of the receptacles that God used to create light and goodness.
These lights are never allowed to dim or go out, and in the case of electric problems, often alternate emergency energy sources are used to prevent it from diminishing.
Though once fueled by oil, most today are electric lights. The ner tamid at Temple Sinai in Worcester, MA is solar powered, symbolizing that synagogue's commitment to reducing dependencies on non-renewable resources.
Christian churches often have at least one lamp continually burning before the tabernacle, not only as an ornament of the altar, but for the purpose of worship. The General Instruction of the Roman Missal in the Catholic Church, for instance, states (in 316): "In accordance with traditional custom, near the tabernacle a special lamp, fueled by oil or wax, should be kept alight to indicate and honour the presence of Christ." The sanctuary lamp is placed before the tabernacle or aumbry in Roman Catholic, Old Catholic, and Anglican churches as a sign that the Blessed Sacrament is reserved or stored. It is also used in Lutheran churches to represent the presence of God. The sanctuary lamp may also be seen in Eastern Orthodox Churches. Other Christian denominations burn the lamp to show that the light of Christ always burns in a sin-darkened world.
Such sanctuary or tabernacle lamps are often coloured red, though this is not prescribed by law. This serves to distinguish this light from other votive lights within the church. In the Catholic Church, though red is often used, a white lamp is considered by most liturgists to be more appropriate. The use of multiple lights, always in uneven numbers, i.e. three, five, seven, or more, in place of a single lamp has now become rarer, though it is still seen in some older Catholic churches and in eastern Christian churches. The lamp may be suspended by a rope or chain over the tabernacle or near the entry of the sanctuary, or it may be affixed to a wall; it is also sometimes placed on a ledge beside the tabernacle or on an individual stand placed on the floor, as seen in the image of St Martin's church, Kortrijk, Belgium in the article Church tabernacle. Oil lamps or candles may be used.
In the United States, the Boy Scout Jewish religious emblem, a medal earned by scouts for meeting certain requirements of religious activity and education, is called the Ner Tamid.