(pl. mikva'ot; lit. a "collection" or "gathering together" of water). Ritual bath. Together with the synagogue and religious school, the mikveh was from ancient times a basic institution of Jewish Community life. It is first mentioned in the Pentateuch (Lev. 11:36) as the exclusive medium for purifying individuals or utensils from the numerous sources of impurity listed there: "Only a spring, cistern, or collection (mikveh) of waters shall be cleansing." Among the sources of impurity were contact with a corpse, childbirth, menstruation, venereal disease, and seminal issue. Without resort to the mikveh, the Jew in Temple times could not participate in any religious ceremony, for which he had to be ritually pure. Remains of some of the numerous baths used by pilgrims have been unearthed in Jerusalem. Even after most of the laws of defilement fell into abeyance with the destruction of the Temple, the ritual bath remained an essential component of family life for observant Jews, since a wife has to immerse herself in it after her menstrual period before cohabitation (see Family Purity). Immersion in a ritual bath is similarly required for initiating proselytes and to purify metal cooking utensils and glassware manufactured by non-Jews. In all these cases, a prescribed benediction must be recited. It is also customary, though not strictly a ritual requirement, for very pious Jews to visit the ritual bath before the Day of Atonement, and adherents of Ḥasidic groups do so before the Sabbath.
A whole tractate of the Mishnah (Mikva'Ot) is devoted to the halakhic requirements for constructing a mikveh, and archeological excavations have uncovered mikva'ot conforming to these regulations at Masada, in ancient synagogues, and even in private homes. The mikveh is always linked to public bathing facilities, since the immersion is only valid if the person concerned has previously scrubbed away every possible speck of dirt. Such dirt constitutes a barrier (ḥatsitsah) to the cleansing power of the ritual bath, physical and spiritual cleanliness being interdependent in Judaism.
However, the rabbis insisted that no bath was to be taken immediately after immersion in the mikveh, only before, to stress the latter's exclusively spiritual power. No scholar was to reside in a community which had no public baths, and even a synagogue could be sold to defray the costs of a mikveh.
The basic requirements for the ritual bath include the source and quantity of the water, the materials from which it is built, and the mode of construction. The source must either be underground water (such as a spring) or rainwater, melted snow, or ice. The ice can have been artificially frozen. Spring water---seas and rivers included---purifies when flowing or moving, but rainwater does so only when stationary in a bath or pool. For this reason, the drainage plug must be tight fitting or, alternatively, the water must be changed by pumping it out of the bath. The water itself must on no account be tapped by human agency through collection in a vessel, but must flow into a built-in or hewn-out (not prefabricated) pool or bath. The pipes, viaduct, or gutter through which the water passes on its way to the bath must have no cavities where the water can collect and must not be made of materials prone to biblical uncleanness (Num. 31:22), but rather of earthenware, stone, concrete, cement, asbestos, or plastic. This requirement can be waived if the water flows across an absorptive material for a length of about 12 inches before entering the bath.
The minimum amount of water collected in the ritually approved manner is 40 se'ah, which the rabbis calculated was needed to facilitate a person's complete immersion. They arrived at this measurement by based on the three dimensions of 1 x 1 cubits square by 3 cubits high (Er. 14b). The equivalent volume in present-day terms might be anything from 292 liters (77 gallons) to 532 liters (140.5 gallons); in most communities, however, 762 liters (201 gallons) is the standard minimum. Once the bath contains this minimum amount, it can purify any volume of ordinary water. In this way, hot and cold water can be added and one or more baths or pools can be joined to the original pure source by opening an aperture between them of at least 1.5 inches in diameter at a minimum height of 32 inches. Medieval European ritual baths chiefly got their water from springs, but the most frequently used model today is based on rainwater collected on the roof and flowing down a gutter into a built-in cistern; this cistern constitutes the original store through which all the other pools in the complex are made ritually fit by the approved means. Since both the construction and the regular functioning of the bath are subject to complicated halakhic regulations, expert rabbinical supervision is needed.
In Israel, the Ministry of Religious Affairs supervises and sponsors the construction of ritual baths. A number of standardized models have thus been developed, ranging from small basic units catering to100-family villages to sophisticated urban complexes provided with the most up-to-date facilities, including a beauty parlor. During the first decade of the State, nearly 500 ritual baths were constructed, mostly in new settlements; today there are over 1,200 ritual baths in Israel, few communities now lacking one. Outside of Israel, the ritual bath is almost exclusively confined to Orthodox communities. Conservative Judaism observes the main traditional laws and insists on tevilah (immersion) for proselytes. Despite some suggestions that lakes, oceans, rivers, and certain types of swimming pools are halakhically fit for immersion, the majority view of all law committees of the Conservative movement has upheld the traditional mikveh---for its historical, symbolic, and deep spiritual meaning. Reform Judaism in the United States considers the mikveh superfluous in the modern age, but outside the U.S. most Reform congregations insist on immersion for their proselytes. See also Ablutions.
