Handwashing in Judaism

Jewish law today prescribes several kinds of hand washing (Hebrew: נטילת ידיים‎‎, netilat yadayim):

In two of these hand washings, water is poured out over one's hands with the aid of a vessel, viz., 1) whenever one wakes from his sleep, and 2) before eating bread. These hand washings are nearly always accompanied with a special blessing prior to concluding the actual act of washing (see infra). Although the minimal quantity of water needed to fulfill one's religious duty is 1/4 of a log (a liquid measure of capacity equal to the bulk or volume of one and half medium-sized eggs), and must be sufficient to cover at least the middle joints of one's fingers, water poured out in excess of this amount is considered praiseworthy in Jewish law. The hand washing made when one leaves the lavatory or latrine, or when one touches his privy parts, or sweat, may be done simply with running tap water (faucet).

The most developed and, perhaps, important of these washings is the washing of hands before eating bread. Such washing of hands is called in Hebrew, netilat yadayim, meaning "the lifting up of the hands." It is looked upon with such rigidity, that those who willfully neglect its practice are said to make themselves liable to excommunication, and bring upon themselves a state of scarcity, and are quickly taken out of the world.

Ten brazen lavers are said to have served the priests in the Temple of Solomon in Jerusalem, their function being merely for cleansing the hands and feet before they commenced their service. A teaching preserved in the compendium of Jewish oral law, the Mishnah, informs its reader that any priest who relieved himself by urinating required the washing of the hands and feet. The use of these lavers did not pertain to the general public, nor to their eating foods with washed hands.

The Mishnah (Tractate Yadayim) is the first to describe the ritual of hand washing outside of the Temple.

The Babylonian Talmud explains that King Solomon enacted hand washing as a safeguard, before one eats of any of the animal sacrifices in the Temple. This enactment was restricted only to washing of hands immediately prior to eating those meat offerings of sacrificial animals (hallowed things) offered in the Temple.

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