הלכות מטמאי משכב ומושב

An unlearned person, even though he is Jewish and observant of the Torah and its mitzvot, is assumed to be impure and his clothes are considered a midras if they come into contact with pure substances. If his clothes touch food or liquids, they are impure. If he touches an earthenware container from the inside, he imparts impurity to it. Terumah should be burnt if such a person touches it, even though his impurity is of doubtful status.
The word of such persons is not accepted regarding the status of pure articles, because they are not knowledgeable regarding the intricacies of the laws of purity and impurity. We continue to operate under this presumption and the person's word is not accepted until he resolves to accept the restrictions of a chavair. What is meant by the restrictions of a chavair that he must resolve to accept? That he be careful with regard to sources of impurity, not to contract impurity from them; that he be careful with regard to pure articles that he not impart impurity to them; that he be careful with regard to washing hands and maintaining their purity; that he not take moist foods from an unlearned person; that he not accept his hospitality; nor offer hospitality to him while the unlearned person is wearing his own garments.

When a person seeks to accept upon himself all the practices of a chavair except one, he is not accepted. If we see he carries out these practices privately in his own home, we accept him and then we teach him the concepts of impurity and purity. If we do not see him conducting himself in this manner privately at home, we teach him and then we accept him.
First, a person is accepted with regard to maintaining the purity of his hands. Afterwards, he is accepted with regard to dealing with pure objects. If he said: "I only accept upon myself, the purity of hands," he is accepted. If he sought to accept the restrictions regarding pure objects, but not those that apply to the purity of hands, we do not accept him, even for pure objects.
When he is accepted, we are cautious with regard to his conduct for 30 days until he learns the intricacies of the laws and is used to dealing with pure objects. Once 30 days have passed since he accepted the customs of a chavair, his clothes are considered as pure and all of his food and liquids are considered as pure. His word is accepted with regard to pure objects like all other chavairim even though he is not a Torah scholar.

Torah scholars are assumed to be chavairim. Their word is accepted regarding pure articles and they do not have to undertake a formal acceptance of the practices of chaveirim. Nevertheless, after the destruction of the Temple, the priests adopted an additional measure of stringency among themselves and they would not give pure objects to anyone, even Torah scholars, until they formally accepted the practices of chaveirim.

When a person seeks to accept the practices of a chavair, he must formalize this acceptance in the presence of three chaveirim. His sons and the members of his household need not formalize this acceptance in the presence of three chaveirim, because he will teach them and train them in the ways of purity. The wife of a chavair, his sons, the members of his household, and his servants are considered like a chavair. If a chavair dies, his wife, his sons, and the members of his household are considered as chavairim until their conduct arouses suspicion.

When the widow of an unlearned person or the daughter of one marries a chavair or the servant of a such a person is sold to a chavair, the woman or the servant must accept the practices of a chavair as at the outset. When, by contrast, the widow of a chavair or his daughter marries an unlearned person or his servant is sold to an unlearned person, there is no need for them to accept the practices of a chavair as at the outset.

When an unlearned person accepts the practices of a chavair, but had pure articles that remained from the time that he was unlearned, although he says: "I know with certainty that they did not contract impurity when others were involved with them," they are forbidden, as was their status initially. If he personally was involved with these pure articles before his status changed, the articles are permitted to him, but they are forbidden to all others.
A chavair may be asked about the state of his pure articles and he may rule in his own favor, that they are permitted. We do not harbor suspicions about him in this context.

When a chavair becomes a tax collector, a collector of customs duty, or the like, he is stripped of his status as a chavair. If he abandons his evil deeds, he is considered as every other person. He must accept the practices of a chavair as at the outset.

When an unlearned person accepted the practices of a chavair and then becomes suspect with regard to a particular matter, he is suspect only with regard to that particular matter. Nevertheless, one who became suspect with regard to a severe matter is suspect with regard to a slighter matter. If he becomes suspect for a slight matter, he is not considered suspect for a more severe matter.

When a chavair becomes suspect with regard to permissiveness in connection with ritually pure articles, e.g., he sold ritually impure foods with the presumption that they were pure, he is no longer considered as trustworthy until it becomes known that he repented completely.

When a person is suspect with regard to the violation of the laws regarding the Sabbatical year or with regard to selling terumah as ordinary produce, he is considered to be suspect with regard to violating the restrictions concerning ritual purity. For a person who is suspect with regard to a Scriptural prohibition is considered suspect with regard to Rabbinic safeguards. And impure foods impart impurity to other entities only by virtue of Rabbinic decree, as will be explained.
Any person who is suspect with regard to a particular matter is, nevertheless, permitted to deliver testimony regarding such a matter with regard to others and to serve as a judge with regard to others. The rationale is that we operate under the assumption that a person will not transgress so that others will benefit.