Miḳweh

Mikveh or mikvah (Hebrew: מִקְוֶה / מקווה, Modern mikve, Tiberian miqwe, pl. mikva'ot, mikvoth, mikvot, or (Yiddish) mikves,lit. "a collection") is a bath used for the purpose of ritual immersion in Judaism to achieve ritual purity.

After the destruction of the Temple, the mikveh's main uses remained as follows:

Most forms of impurity can be nullified through in any natural collection of water. However, some impurities, such as a zav, require "living water," such as springs or groundwater wells. Living water has the further advantage of being able to purify even while flowing, as opposed to rainwater which must be stationary in order to purify. The mikveh is designed to simplify this requirement, by providing a bathing facility that remains in ritual contact with a natural source of water.

In Orthodox Judaism, these regulations are steadfastly adhered to and, consequently, the mikveh is central to an Orthodox Jewish community; they formally hold in Conservative Judaism as well. The existence of a mikveh is considered so important in Orthodox Judaism that an Orthodox community is required to construct a mikveh before building a synagogue, and must go to the extreme of selling Torah scrolls or even a synagogue if necessary, to provide funding for the construction.

In the Hebrew Bible, the word is employed in its broader sense but generally means a collection of water.

Before the beginning of the first century BCE, neither written sources, nor archaeology gives any indication about the existence of specific installations used for ritual cleansing. Mikvoth appear at the beginning of the first century BCE, and from then on ancient mikvoth can be found throughout the land of Israel as well as in historic communities of the Jewish diaspora.

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