impure with an impurity lasting until the evening. There are cases where three things can be rendered impure in succession by a corpse, two of those things being rendered impure with a seven-day impurity and the remaining thing with an impurity lasting until the evening. And there are cases where four things can be rendered impure in succession by a corpse, three of those things being rendered impure with a seven-day impurity and the remaining thing with an impurity lasting until the evening. The Mishnah taught that a case of corpse contamination of two things in succession (where one is rendered impure with a seven-day impurity and one being rendered impure with an impurity until the evening) occurs when a person who touches a corpse is rendered impure with a seven-day impurity, as says, "He who touches the corpse of any human being shall be unclean for seven days." The Rabbis considered a corpse to have the highest power to defile, and regarded a corpse as an originating source of impurity, a "father of fathers of impurity" (, avi avot ha-tumah). Thus the Mishnah taught that a corpse can confer a generating impurity, a "father of impurity" (, av ha-tumah), on a person with whom it comes in contact. A "father of impurity" (, av ha-tumah) requires a seven-day cleansing period. And then a second person who touches the first person who touched the corpse is rendered impure with an impurity lasting until the evening, as says, "the person who touches him shall be unclean until evening." The "father of impurity" (, av ha-tumah) — in this case, the person who first touched the corpse — can, in turn, confer a first-grade impurity (, rishon l'tumah), which requires a cleansing period lasting only until sundown. In sum, in this case, the first person acquired a "father of impurity" (, av ha-tumah) from the corpse, and the second person acquired a first-grade impurity (, rishon l'tumah) from the first person. Resh Lakish derived from “This is the Torah, when a man shall die in the tent,” that words of Torah are firmly held by one who kills himself for Torah study. The Mishnah taught that a case of corpse contamination of three things in succession (where two are rendered impure with seven-day impurity and one with an impurity until the evening) occurs when a utensil touching a corpse becomes a "father