[m., pl. “maimot”]; water; involved as a primary element on the Second and on the Third Days of Creation; when G-d separated the “upper” from the “lower” waters, and when G-d gathered them into one place, calling them “Yamim,” Seas.
A human being is delivered at birth in a bag of waters; some say that one never forgets this experience; to drink water is one of the primary needs of life.
In Biblical and Temple times, the method of becoming spiritually “clean” after having become spiritually “unclean;” for example, by contact with a human corpse, involved being sprinkled with the ashes of a “Parah Adumah,” a red heifer (cow) (regarded as a Divine decree, without need of explanation, though symbolic meanings have been attached), dissolved in water.
Another necessary ingredient in the process of regaining purity was and is immersion in a “Mikvah,” a pool of “mayim chayim,” “living (non-stagnant) waters.” The word “Mikvah” is based on the root “hope.” In the absence of a Mikvah, the ocean, or a river or a flowing lake will serve.
The Mikvah is used as an element of “Teshuvah,” Repentance.
In marital law, the Mikvah is also a vital component. Those laws, regarding Sexual Discipline in Marriage, are generally referred to as “Taharat HaMishpacha,” or family purity.