Mishneh Torah (Rambam) משנה תורה

Anyone who eats bread over which the blessing hamotzi is recited must wash his hands before and after partaking of it.This applies even when the bread one eats is not sacred food. Although a person's hands are not dirty, nor is he aware that they have contracted any type of ritual impurity, he should not eat until he washes both his hands. Similarly, before [partaking of] any food dipped in liquid, one must wash one's hands.

Whenever a person washes his hands - whether before eating, before the recitation of the Shema, or before prayer - he should recite the following blessing beforehand: "[Blessed are You...] who sanctified us with His commandments and commanded us concerning the washing of hands." This is a Rabbinic mitzvah that we have been commanded by the Torah to follow, as [Deuteronomy 17:11] states: "[Do not stray...] from all the laws that they direct you." A blessing should not, however, be recited before washing after eating, for this was instituted only as a protective measure. This rationale, however, obligates a person to be more careful in the observance of this practice.

Washing hands between one course and another is a matter of choice. If one desires, one may wash; if not, one need not. There is no obligation to wash before partaking of unconsecrated fruit, whether before eating or afterward. [On the contrary,] whoever washes his hands before partaking of fruit is considered among the haughty. Whenever bread [is eaten] with salt, it is necessary to wash one's hands afterward, lest it contain Sodomite salt or salt that resembles Sodomite salt, and [after eating,] one [inadvertently] pass one's hands over one's eyes and blind them. This - [the possibility of acrid] salt - is the reason why we are obligated to wash after eating. In an army camp, [the soldiers] are not obligated to wash before eating, because they are involved in the war. They are, however, obligated to wash afterwards because of the danger involved.

To what point should one's hands be washed? To the wrist. How much water should be used? A [minimum of a] revi'it for each pair of hands. Anything that is considered an intervening substance [and thus invalidates] a ritual immersion is also considered an intervening substance with regard to washing hands. All liquids that may be included in the measure of a mikveh may be included in the measure of the revi'it [necessary for the washing of hands].

Whoever had to wash his hands and [instead] immersed them in the water of a mikveh need not do anything else. If he immersed them in a body of water that does not have the required measure of a mikveh, or in water that has been poured onto the ground, he has not accomplished anything. Water that is poured [by man] can purify hands only when it is poured over them.

Everyone who washes his hands must show concern for four matters: the water itself - that it not be unacceptable for washing hands, its measure - that there be a revi'it for each pair of hands, the container - that one wash from a container, the individual pouring - that the water come from the power of a person who pours it.

There are four matters that render water unacceptable: a change in its color, its being left open, its having been used for work, and its becoming spoiled to the point that an animal would not drink from it. What is implied? Water whose color changes becomes unacceptable whether it is contained [in a pool] in the ground or in a container, or whether it changed because of something that fell into it or because of the place where it is contained. Similarly, if the water was left uncovered in a manner that causes it to become forbidden to be drunken, it is unacceptable for washing hands.

Any water that was used for a task is considered as sewage water and is unfit to use for washing hands. What is implied? Water that has been drawn from its source, which was used to wash utensils, to dip one's bread in, or the like, whether [it was stored] in a container or [in a pool] in the ground, becomes unacceptable for washing hands. If one uses the water to wash clean utensils or new ones, it does not becomes unacceptable. Water in which a baker dips crackers is unacceptable. In contrast, water from which [he removes some] to baste the dough when kneading it is acceptable. It is the water that he removes that was used for a task; the water from which he removed it remains acceptable [as before].

All water that becomes unfit for a dog to drink - e.g., bitter [water], salty [water], very murky [water], foul-smelling [water] - which is contained in a vessel may not be used for washing hands. If [such water] is [contained in a pool] in the ground, one may immerse one's hands in it. [The following rules apply to] the hot springs of Tiberias. In their [natural] place, one may immerse one's hands in them. If, however, one removed them with a container or diverted a stream of them into another place, they may not be used for either the first or the final washing of the hands, because they are not fit for an animal to drink.

One may pour water over one's hands a little at a time until one has poured out the entire amount. If, however, one poured out the entire revi'it at one time, it is acceptable. Four or five people may wash with a single pouring while they are standing next to each other or with their hands above each other's, provided: a) they leave space between their hands for the water to enter, and b) there is enough water in that pouring to provide each one with a revi'it.

One may not use the following to wash one's hands: the sides of vessels, the base of a samovar, pieces of earthenware, or the covering of a jug. Should one modify such a covering to use for washing, it is acceptable. Similarly, a wine-pouch that was modified may be used for the washing of hands. In contrast, a sack or a basket - [although] they have been modified - may not be used to wash hands. One may not hold water in one's hands and pour it over a colleague's [hands], because one's hands are not a vessel. Vessels that have been broken to the extent that the laws of ritual impurity no longer apply to them may not be used to wash hands, because they are considered to be broken vessels.

All vessels, even those made from cow dung or earth, may be used to wash hands, provided they are whole. A vessel that cannot contain a revi'it or a vessel that does not contain a revi'it may not be used for the washing of hands.

All people are acceptable to pour water over one's hands, even a deaf-mute, a mentally incapable person, or a minor. If no one else is present, one should hold the vessel between one's knees, and thus pour it out over one's hands; lean a jug over so that the water will fall out over one's hands; or pour the water over each of one's hands individually. It is acceptable if a monkey pours water over one's hands.

When a person pours water into a trough by hand or by using a pulley, and afterwards the water flows out from it through an irrigation channel that brings the water to vegetables or to animals, it is not acceptable for one to place one's hands in the trough and have the water pass over them, because the water is not coming from "the power of a giver." If one's hands were close to the place where the bucket is poured out so that the water passes over one's hands because of the power of a human being, the washing is acceptable.

When there is a doubt with regard to the water [used to wash one's hands] - e.g., whether it had been used for other tasks or not, whether it contained the required quantity or not, whether it [the water itself] is ritually pure or not, and, similarly, when a person has a doubt whether he washed his hands or not, [in all these instances,] his hands are considered to be pure. In all instances where doubt arises concerning the ritual purity of hands, the hands are considered to be pure.

When washing before eating, a person should raise his hands upward so that that water will not flow past the wrist, and then return and make the hands impure. In contrast, when washing after eating, a person should hold his hands downward so that all the power of the salt should be rinsed away off one's hands. Before eating, one may wash into a container or onto the ground. After eating, one should wash only into a container. Before eating, one may wash with hot water or with cold water. After eating, one should not wash with hot water - i.e., water that will scald one's hands. It will not [serve the purpose of] removing filth, because one cannot rub one's hands together with it. If the water is merely warm, it may be used for washing after eating.

A person may wash his hands in the morning and stipulate that [the washing will be effective] for the entire day. Thus, he will not have to wash before each time he eats. [This rule applies] only when he does not divert his attention from his hands. If, however, he diverts his attention from them, he must wash them whenever it is required.

A person may wrap his hands in a cloth and eat bread or food dipped in liquid although he did not wash his hands. A person who feeds others need not wash his hands. The person who eats, however, must wash his hands, although another person puts food into his mouth and he does not touch the food at all. Similarly, a person who eats with a fork must wash his hands.

It is forbidden to feed someone who did not wash his hands even if one puts the food directly into his mouth. It is forbidden to treat the washing of hands with disdain. Our Sages have authored many commands and warnings about this manner. Even when one has a minimum amount of water to drink, one should wash one's hands with a portion, eat, and drink the remainder.

[After washing,] a person must dry his hands before eating. Anyone who eats without drying his hands is considered to have eaten impure bread. Similarly, whenever a person washes his hands after eating, he should dry them and then recite grace. One should recite grace directly after washing one's hands. No interruptions should be made. It is even forbidden to drink water after washing one's hands after eating until one recites grace.