Zavim, Chapter Five, Mishnah One
1) One who touches a zav, or whom a zav touches, who moves a zav or whom a zav moves, defiles by contact food and liquids and vessels that are rinsed, but not by carrying.
2) A general principle was stated by Rabbi Joshua: anyone that defile garments while still in contact [with their source of uncleanness] also defiles foods and liquids so as to become [unclean] in the first grade, and the hands so that they become [unclean] in the second grade; but they do not defile people or earthenware vessels.
3) After they separated from their source of uncleanness they defile liquids so as to become [unclean] in the first grade, and food and the hands so that they become [unclean] in the second grade, but they do not defile garments.
Section one: A zav defiles through contact or through moving something or being moved by something. This mishnah discusses the level of impurity of the person whom he defiled. Such a person defiles food, liquids and vessels that “are rinsed” meaning vessels that can be purified by being put in a mikvah. This would include basically all vessels except earthenware, which can’t become pure in a mikveh. The person defiled by a zav defiles only through actual contactshe/he does not defile through carrying. She also does not defile other peoplejust food and things.
Section two: Rabbi Joshua formulates a general principle meant to aid in determining the level of impurity of certain people mentioned in the Torah. The Torah says about certain people, for instance one touched by a zav, that he must wash his clothes (see for instance Leviticus 15:5-11, 21-22, 27). When he is actually touching the zav or something the zav laid upon, his level of impurity is relatively high. He defiles food and liquids so that they have first degree impurity. And if he touches the hands of another person he gives them second degree impurity (we will return to the topic of hand impurity in the next tractate). However, he doesn’t defile people or earthenware vessels, as was stated in section one.
Section three: This is a continuation of Rabbi Joshua’s general principle. Once the person has separated from the source of impurity, his ability to defile is lowered. He still defiles liquids so that they have first degree impurity. This is because liquids have a higher degree of susceptibility to impurity. However, he only defiles food and hands so that they have second degree impurity. This means that the food is only affected if it is terumah. If it is regular produce, it is unaffected. These people do not defile garments or any other vessels for they are treated as if they have first degree impurity and people with first degree impurity do not defile vessels or people.