Written by: Allan Nadler
While communal services with a minyan are most commonly held in synagogues (the Greek term for the original Hebrew, beit knesset, or House of Assembly), which are today often referred to as temples by Reform and some liberal Conservative congregations, any "clean" room (i.e., one not defiled by any form of filth or idolatrous images) that contains Torah scrolls and in which a minyan worships attains the status of a Makom Kadosh, literally a Holy Space, suitable for public prayer. There is nothing intrinsically holy about synagogues, beyond the presence of the Torah and the quorum of worshipers using it as a place of religious devotion. This is largely because all traditional synagogues, both in Israel and the Diaspora since the destruction of Solomon's Temple in Jerusalem, have been considered but temporary places of worship-in-exile; these will ultimately become entirely superfluous once the Jerusalem Temple is re-built, during the Messianic Era. Reform Judaism initially rejected this traditional messianic outlook, and partly for that reason began to refer to synagogues (a term connoting a utilitarian meeting house, as opposed to a place of intrinsic sanctity) as temples.
It is precisely because it is believed that only the Jerusalem Temple is endowed with essential, or intrinsic, holiness, while synagogues are seen as no more than temporary places in which Jews can assemble for prayer and whose sanctity is entirely utilitarian, that there are only the barest of regulations governing the synagogue architecture and aesthetics. The cardinal rule regarding synagogue aesthetics is the complete ban on the presence of any images, or icons, of either God or humans. Judaism's rigid iconoclasticism can be traced back to the second of the Ten Commandments, which prohibits the creation and worship of any "graven images." This stylistic openness, combined with the worldwide dispersal of the Jewish Diaspora, has resulted in a plethora of architectural styles, most often greatly influenced by the prevailing trends in the surrounding gentile communities. It was not until the rise of the grand Reform Temples in early 19th-century Europe that Jewish houses of worship were obviously designed to emulate the style of Christian Churches, both externally and internally.