The Hebrew term for synagogue is Beit Knesset - בית כנסת ("House of Assembly"), not to be confused with the Knesset, which is the Israeli parliament. Some congregations use the term Beit Tefila - בית תפילה ("House of Prayer").
Synagogues usually have a large hall for prayer (the main sanctuary), smaller rooms for study, and sometimes a social hall and offices. Some have a separate room for Torah study, called the Beit midrash - בית מדרש ("House of Study").
Many Orthodox and Conservative Jews in English-speaking countries use the Yiddish term "shul." The use of "synagogue" is reserved for formal occasions. Spanish and Portuguese Jews call the synagogue an esnoga. Persian Jews and Karaite Jews use the term Kenesa, which is derived from Aramaic. Reform and Conservative congregations in the United States sometimes use the word "temple."
Before the destruction of the Second Temple in 70 CE, communal prayers centered around the korbanot ("sacrificial offerings") brought by the kohanim ("Jewish priests") in the Holy Temple. The all-day Yom Kippur service, in fact, was an event in which the congregation both observed the movements of the kohen gadol ("Jewish high priest") as he offered the day's sacrifices and prayed for his success.
The destructions of Solomon's Temple, and later the Second Temple, and the dispersion of the Jews into the Jewish diaspora, threatened the nation's focus and unity. At the time of the Babylonian captivity the Men of the Great Assembly began the process of formalizing and standardizing Jewish services and prayers that would not depend on the functioning of the Temple in Jerusalem. Rabbi Yohanan ben Zakkai, one of the leaders at the end of the Second Temple era, promulgated the idea of creating individual houses of worship in whatever locale Jews found themselves. This contributed to the concept of "portable Judaism," which was part of what contributed to the saving of the Jewish people by maintaining a unique identity and way of worship, according to many historians. Thus, even now, whenever any group of ten men comes together, they form a minyan, and are eligible to conduct public prayer services, usually in a synagogue.
In Eastern Europe, synagogues were established by like-minded groups of people. Such a synagogue was known as a kloiz, and was often delineated by the professions of its worshippers: e.g. "the tailor's kloiz," the "water-carrier's kloiz," etc. One kloiz which still bears that name today is the Breslov kloiz built by Nathan of Breslov in the city of Uman, Ukraine in 1834. Today, this kloiz accommodates worshippers in the annual Breslover Rosh Hashana kibbutz (prayer gathering).
The architectural shapes and interior designs of synagogues vary greatly. Other local religious buildings and national culture usually influence synagogue architecture.
Traditional and Orthodox synagogues
Orthodox Judaism has considered synagogue construction over the last two thousand years as following the outlines of the original Tabernacle, which was also the outline for the temples in Jerusalem. The Orthodox synagogue usually contains the following features:
An ark – called the Aron Ha-Kodesh – ארון קודש, the Holy Ark by Ashkenazim and heikhal – היכל [temple] by Sephardim – where the Torah scrolls are kept. The Ark in a synagogue is positioned in such a way that those who face it, face towards Jerusalem. Thus, sanctuary seating plans in the Western world generally face east, while those east of Israel face west. Sanctuaries in Israel face towards Jerusalem. Occasionally synagogues face other directions for structural reasons; in such cases, some individuals might turn to face Jerusalem when standing for prayers, but the congregation as a whole does not. The ark is reminiscent of the Ark of the Covenant which contained the tablets with Ten Commandments. This is the holiest spot in a synagogue, equivalent to the Holy of Holies. The ark is often closed with an ornate curtain, the parokhet - פרוכת, outside or inside the Ark doors.
- A large, raised, reader's platform called the bimah - בימה - by Ashkenazim and tebah by Sephardim, where the Torah scroll is read and from where the services are conducted in Sephardi synagogues.
- A continually-lit lamp or lantern, usually electric, called the ner tamid (נר תמיד), the "Eternal Lamp," used as a reminder of the western lamp of the menorah of the Temple in Jerusalem, which remained miraculously lit always.
- A candelabrum specifically lit during services commemorating the full Menorah.
- A pulpit facing the congregation for the use of the rabbi, from and a pulpit or amud - עמוד (Hebrew for "post" or "column") facing the Ark where the Hazzan stands while leading the prayer service.
- A mechitzah dividing the men's and women's seating areas. In places where there is not enough room to seat both sexes on one floor, the women's section is located on a balcony.
- A synagogue may be decorated with artwork, but in the Rabbinic and Orthodox tradition, three-dimensional sculptures and depictions of the human body are not allowed, as these are considered akin to idolatry.
Until the 19th century, the synagogue interior was laid out with both a spiritual and a communal focus. In an Ashkenazi synagogue, all seats faced the aron kodesh (Ark) in which the Torah scrolls were housed. In a Sephardi synagogue, seats were arranged around the perimeter of the sanctuary, but when the worshippers stood up to pray, everyone faced the Ark. The Torah was read on a reader's table located in the exact center of each sanctuary, echoing the manner in which the Children of Israel stood around Mount Sinai when they received the Torah. The leader of the prayer service, the Hazzan, stood at his own lectern or table, facing the Ark.
Another related place of worship which is often a small synagogue is the shtiebel (שטיבל, pl. shtiebelekh or shtiebels, Yiddish for "little house") that is frequently used by and preferred by Hasidic and Haredi Jews. A shtiebel may sometimes be a room in the private home of a Hasidic Rebbe, or a place of business which is set aside for the express purpose of prayer. It may or may not offer the communal services of a synagogue.
In the US, there are well over 1200 Orthodox congregations, including over 1000 of which are affiliated with the Orthodox Union (OU), and 150 with the National Council of Young Israel, as well as a great number associated with Agudath Yisrael, a widespread movement often identified with "black-hatter" Orthodox, especially Chassidim.
Reform synagogues and temples
The German Reform movement which arose in the early 1800s made many changes to the traditional look of the synagogue, keeping with its desire to simultaneously stay Jewish yet be accepted by the host culture. The first Reform synagogue, which opened in Hamburg in 1811, featured changes that made the synagogue look more like a church. These included: the installation of an organ to accompany the prayers (even on Shabbat—when musical instruments are proscribed by halakha), a choir to accompany the Hazzan, and vestments for the synagogue rabbi to wear.
In following decades, the central reader's table, the bimah, was moved to the front of the Reform sanctuary—previously unheard-of in Orthodox synagogues. The rabbi now delivered his sermon from the front, much as the Christian priests delivered their sermons in a church. Bar mitzvah ceremonies, held at age 13, were followed up with "confirmation" ceremonies at age 16/17. Following the teaching of Rabbi Mordechai Kaplan, Bat Mitzvah ceremonies were introduced for girls. The synagogue was renamed a "temple," to emphasize that the movement no longer looked forward to the rebuilding of the Temple in Jerusalem.
With the emigration of German Reform Jews to America in the mid-nineteenth century, the synagogue exterior also changed. The wealthy German Jewish immigrants built grandiose temples modeled after churches. Temple Emanu-El, the oldest Reform congregation (founded in New York City in 1845), constructed an imposing Moorish-style building, with towering limestone walls, on Fifth Avenue in 1929. The architecture rivaled the design of the great cathedrals of Europe. Inside, arched walls and Tiffany and stained-glass windows accentuated the 2,500-seat main sanctuary and a smaller. Reform temples built in other American cities displayed Romanesque, Byzantine, and other grand, church-like designs. As of 2005, the Reform movement in the US encompassed approximately 900 congregations.
The Conservative movement, which also developed in Europe and America in the 1800s, rejected Reform as being too liberal and Orthodoxy as being too outdated. However, its synagogue design is not consistent. Sometimes, Conservative synagogues resemble Reform temples—complete with organ. Other times they more closely resemble Orthodox synagogues, but without a mechitza, the dividing barrier between men and women. There are approximately 750 Conservative synagogues in the US today.
The Reconstructionist movement, which arose in America in the latter half of the 20th century, counts less than 100 synagogues worldwide. In keeping with a Reconstructionist Jewish spirit of liberalism, Reconstructionist synagogues are not as traditionalist as Conservative Judaism in the design of the synagogue and do not use the mechitza. The congregation decides communally how much traditional Judaic imagery and symbols are appropriate. Reconstructionist Jews generally do not call their houses of worship "temples", as Reform Jews often do.
In Israel and regions of the Jewish diaspora archaeologists have uncovered many ruins of synagogues from thousands of years ago. The small ruined synagogue at Masada is one of the most well-documented; it dates from the time of the Second Temple. Synagogues have also been discovered in Egypt and on the island of Delos which predate the synagogue at Masada.
The Dura-Europos synagogue (in today's Syria) is considered the world's oldest preserved Jewish synagogue.
The oldest active synagogue in Europe is the Alteneushul (Old-New Synagogue) in Prague, Czech Republic, which dates from the 13th century. The Altneushul was the pulpit of the great Rabbi Yehuda Loew, the Maharal, and his creation, the golem of Prague, is rumored to be hidden within the synagogue. During Kristallnacht on November 9-10, 1938, the Nazis in Germany and Austria destroyed or significantly damaged 1,574 synagogues, which included many of the greatest synagogues of Europe. Many were also destroyed or fell into disrepair during the Nazis' conquest of Europe, during which many Jewish communities were wiped out.
The Hurba Synagogue, located in the Jewish Quarter of the Old City of Jerusalem, was Jerusalem's main synagogue from the 16th century until 1948, when it was destroyed by the Arab Legion. After the Six-Day War, an arch was built to mark the spot where the synagogue stood. Reconstruction is now under way, in keeping with plans drawn up by architect Nahum Meltzer. The Ramban Synagogue, founded by Nahmanides in 1267, is the oldest active synagogue in the Old City. See also Synagogues in Jerusalem.
The Paradesi Synagogue in the old city of Kochi, Kerala State, India, dates from 1568.
The Barbados Nidhe Israel Synagogue ("Bridgetown Synagogue") located in the capital city Bridgetown. First built 1654. Destroyed in the hurricane of 1831, reconstructed in 1833.
The Amsterdam Esnoga is a Sephardic synagogue The Netherlands. It was founded by ex-Maranos (Portuguese Crypto-Jews) in 1675.
The Touro Synagogue in Newport, Rhode Island modeled after the Esnoga in Amsterdam, is the oldest Jewish house of worship in North America. It was built in 1759 for the Jeshuat Israel congregation, which was established in 1658. In 1787 this sanctuary was the location where the British commanders surrendered at the end on the revolutionary war to General George Washington.
The Bialystoker Synagogue on New York's Lower East Side, is located in a landmark building dating from 1826 that was originally a Methodist Episcopal Church. The building is made of quarry stone mined locally on Pitt Street, Manhattan. It is an example of Federalist architecture. The ceilings and walls are hand painted with zodiac frescos, and the sanctuary is illuminated by 40-foot stained glass windows. The Bima and floor-to-ceiling Ark are handcarved.
The Snoga Synagogue in Willemstad, Curaçao, Netherlands Antilles was built by Sephardic Portuguese Jews from Amsterdam and Recife, Brazil. It is modeled after the Esnoga in Amsterdam. Congregation Mikvé Israel built its synagogue in 1692, and it was reconstructed in 1732.
The largest synagogue in the world is the Belz World Center in Jerusalem, Israel. Construction took 16 years. The main Sanctuary seats 6,000. The second largest synagogue is Congregation Emanu-El of the City of New York, a Reform house of worship located on Fifth Avenue, New York City, with an area of 3,523 m², seating 2,500.
The Dohány Street Synagogue or Great Synagogue in Budapest, Hungary is the largest synagogue in Europe and the third largest in the world, after the Belz World Center and the Congregation Emanu-El in New York City. It seats 3,000 people and is a centre of Neolog Judaism and hosts the Jewish Museum of Budapest. The building was built in 1854-1859 according to the plans of architect Ludwig Förster.
Other large synagogues include the Great Synagogue and the Great Synagogue in Plzeň, Czech Republic; the Orthodox synagogue in Košice, Slovakia; Synagogue in Novi Sad, Serbia, the Sofia Synagogue in Sofia, Bulgaria. The synagogue of Congregation Beth Israel in West Hartford, Connecticut, has been placed on the National Register of Historic Places.