Mikvah
A Mikvah (or Mikveh) is a Jewish ritual bath used for immersion in a purification ceremony. Traditionally, the mikvah was used by both men and women for various purposes. Everyone was required to go to the mikvah upon coming into contact with the dead, lepers and Nazirites were required to immerse in the mikvah upon being healed or completing their vows, priests were required to immerse before performing certain Temple rites, men were required to immerse after having a nocturnal emission, and women after giving birth or menstruating. Today, among Orthodox Jews, only women are still required to go to the mikvah after childbirth or menstruation before they have sexual relations with their husbands, and both men and women immerse themselves on the day of their wedding. Nevertheless, some men continue to go to the mikvah regularly, either daily, weekly, or before Yom Kippur.The rules regarding the construction of mikvahs are complicated. The immersion itself must take place in mayyim chayyim ("living water"), i.e., water that moves. Rivers or lakes can therefore be used for immersion, but standard bathtubs cannot. Alternately, rain water can also be used, and is the source of most mikvah water today. Though a certain amount of rainwater is required, this can be augmented with regular tap water, which has a connection to mayyim chayyim. This later formula is often used so that the water used for immersion can be frequently changed. A pool of rainwater is connected with a duct to a regular bathing pool, and the duct is closed to empty and replace the regular water without replacing the rain water.
Immersion requires that the water cover the entire body. All clothing, jewelry, and even bandages must be removed, and the hair must be combed straight so that there are no knots. In contemporary mikvahs for women, there is usually a "mikvah lady" to watch the immersion and ensure that the woman has been entirely covered in water.
Samples of ancient mikvahs dating from Temple times can be found through Israel and Palestine.