Keritot, Chapter Three, Mishnah Two
This mishnah begins discussing the topic of how to divide one act of transgressing into several transgressions, such that a person would be considered as having transgressed only one, or join separate acts into one act such that a person would be liable independently for each act. This is a topic of immense interest to the rabbis and they will continue to discuss it throughout the chapter and even in chapter four.
1) If one twice ate forbidden fat in one spell of unawareness, he is liable to but one hatat.
2) If one ate forbidden fat, blood, piggul and notar in one spell of unawareness, he is liable for each kind.
3) This is an instance where different kinds [of food] are more stringent than one kind.
4) In the following instance, however, one kind [of food] is more stringent than several kinds: if one ate half an olive-size and then again half an olive-size, both in one spell of unawareness, if of one kind he is liable, if of two kinds, he is exempted.
Section one: If a person ate forbidden fat twice, but both times he was unaware of what he was doing, for instance he didnt know that what he was eating was forbidden fat, he is liable for only one hatat. As long as he was not informed of his sin in between the acts, this counts as only one sin.
Section two: However, if he ate different kinds of prohibited substances within one period of unawareness, meaning he was not told in between each item that what he is eating is prohibited, he is liable for a hatat for each kind of prohibited substance. This is because each is its own prohibition. Piggul is sacrificial meat that was offered with a disqualifying intention, and notar is remnant, sacrificial meat left over beyond the time when it must be eaten.
Section three: As the Mishnah so often does, it compares the above case with another case, noting that sometimes eating differently prohibited substances is treated more stringently, and sometimes it is treated more leniently. The above case is one in which it was treated more stringently.
Section four: In contrast, if a person eats half of an olives worth of one prohibited substance and then another half of an olive of the same substance, he is liable for a hatat, because he ate one olives worth, the amount necessary to be liable. If the two half-olives were of different substances, then he is exempt because he didnt eat an olives worth of a single prohibited substance.