1) A "KEMITZAH" THAT IS LACKING
QUESTION: The Mishnah teaches that if the Kohen performs Kemitzah and finds among the flour in his hand a pebble, a seed, salt, or a piece of incense, the Kemitzah is Pasul because the flour is lacking due to the presence of the foreign object. The Mishnah also teaches that any Kemitzah that contains too much or too little flour is Pasul. The Mishnah explains that a Kemitzah with too much flour is when the Kohen takes so much flour that it protrudes out of the sides of his fingers. A Kemitzah with too little flour is when the Kohen performs the Kemitzah with only the tips of his fingers.
Why does the Mishnah need to give an example of a Kemitzah with too little flour, when the Mishnah itself already mentions such a case -- a Kemitzah in which the Kohen finds a foreign object? (TOSFOS)
ANSWER: There is a basic difference between the case of a Kemitzah which contains a foreign object and the case of a Kemitzah performed with the tips of the fingers. When the Kemitzah is performed correctly but is missing some of the flour, the Korban Minchah is considered to have had a Kemitzah done for it, but since that Kemitzah is Pasul the Minchah itself is Pasul. This is similar to a case in which a Zar (non-Kohen) performs the Kemitzah. The Kemitzah is considered to have been done, but since it is Pasul the Minchah is Pasul.
In contrast, when the Kohen performs the Kemitzah with the tips of his fingers, it is considered as though no Kemitzah was done at all. The Korban Minchah is Pasul not because its Kemitzah is Pasul, but because no Kemitzah was done at all. It is as if the Kohen took a spoonful of flour from the Minchah instead of doing a proper procedure of Kemitzah.
What is the difference between a Minchah that is Pasul because its Kemitzah is Pasul, and a Minchah that is Pasul because it had no Kemitzah done to it? The difference is that if a Zar performs the Kemitzah, the Minchah is Pasul and it does not help to throw the Kemitzah flour back into the Minchah. Since a Kemitzah was performed in an invalid manner, it cannot be redone. In contrast, when one takes a spoonful of flour from the Minchah, the act is not considered an act of Kemitzah at all and the flour may be thrown back into the Minchah and a proper Kemitzah performed. (This difference is according to the view of the Chachamim who argue with Ben Beseira.)
Accordingly, it is clear why the Mishnah gives another example of a Kemitzah that is lacking. The first case of a Kemitzah that is lacking is a continuation of the Mishnah's list of Pesulim, which are subject to the Machlokes between the Chachamim and Ben Beseira (see TOSFOS to 10b, DH Kamatz). The second case of a Kemitzah that is lacking is a new case in which the Kemitzah was not performed properly (either the hand was open too wide, or the hand was closed too much). In this case, even the Chachamim agree that one may put the flour back into the Minchah and perform a proper Kemitzah, since it is not considered as though an act of Kemitzah was performed.
An allusion to this difference may be found in the words of the RAMBAM. The Rambam records the Mishnah's first case (a foreign object found in the Kemitzah) in Hilchos Pesulei ha'Mukdashin (11:3), among all of the other Pesulim listed in the Mishnah. The Rambam does not record here the case of a Kemitzah performed with the tips of the fingers. Rather, the Rambam alludes to it in Hilchos Ma'aseh ha'Korbanos (13:13), where he explains exactly how the Kemitzah process is performed. The KESEF MISHNEH there explains that the Rambam's intention is to teach that a Kemitzah done with hands that are too open, or a Kemitzah done with the tips of one's fingers, is not an act of Kemitzah. These cases do not belong in Hilchos Pesulei ha'Mukdashin since they are not acts of an invalid Kemitzah. Rather, they are not acts of Kemitzah altogether and they do not qualify as "Ma'aseh ha'Korbanos" (acts of the Avodah of a Korban). (See MINCHAS AVRAHAM.) (Mordechai Zvi Dicker)
2) RETURNING THE FLOUR OF AN INVALID "KEMITZAH" TO THE MINCHAH
QUESTION: The Gemara quotes Rav who says that a Zar who performs an act of Kemitzah should return the flour to the rest of the Minchah (so that a Kohen may perform a proper Kemitzah). The Gemara concludes that Rav's ruling follows the opinion of Ben Beseira, who says in the Mishnah (6a) that when a Kohen performs the Kemitzah with his left hand (an improper way to perform the Kemitzah), he should return the flour to the Minchah and perform the Kemitzah again properly. The Gemara asks that if Rav's ruling follows the view of Ben Beseira, then what is he adding to what Ben Beseira himself says in the Mishnah?
The Gemara answers that Rav is teaching that according to Ben Beseira, one may return the flour of an invalid Kemitzah and redo the Kemitzah in any case of an invalid Kemitzah, and not merely in the case of a Kemitzah that was performed with the left hand. One might have thought that the Pesul of performing the Kemitzah with the left hand is a weaker form of a Pesul, since there is an Avodah which is valid when performed with the left hand (that is, the Avodah of the Ketores on Yom Kippur).
According to the Gemara's answer, a question remains on the Mishnah itself. Why does the Mishnah record the dispute between Ben Beseira and the Chachamim only in the case of a Kemitzah performed with the left hand? If, as Rav asserts, the dispute applies in all cases of an invalid Kemitzah, then the Mishnah should not record the dispute merely with regard to a Kemitzah performed with the left hand, but with regard to all of the Pesulim. (TOSFOS 6a, DH Ben Beseira, SHITAH MEKUBETZES 6a, #34)
ANSWER: The BRISKER RAV (cited by the MINCHAS AVRAHAM) explains as follows. There are two lines of reasoning for why a Kemitzah cannot be redone once it was done improperly. One approach is that a Kemitzah done improperly causes a Pesul to the Minchah. Once the Minchah has become Pasul, performing another Kemitzah cannot make it valid. According to this approach, performing Kemitzah with the left hand might be considered a weaker Pesul and might not cause a Pesul to the Minchah itself, and thus the flour may be returned to the Minchah. (See RASHI to Zevachim 63b, DH she'Yachzir, who writes that "one may return the Kometz to the remaining flour and we do not say that it has already become Pasul.")
The second line of reasoning for why an invalid Kemitzah may not be returned to the Minchah is as follows. When a Kohen performs a valid Kemitzah, may he return the Kemitzah to the pan and perform another Kemitzah? The answer is that he obviously may not redo the Kemitzah, because the Kemitzah that is in his hand has already been established as the Kemitzah of this Korban and the rest of the flour has become the Shirayim, and the status of each part of the flour cannot be changed. (See RASHI to Yoma 29b, DH Kli Shares, who writes this explicitly.)
What is Ben Beseira's reason for ruling that an invalid Kemitzah may be returned to the Minchah and rectified? Ben Beseira maintains that an invalid Kemitzah does not establish the status of the flour taken as the Kemitzah and the remaining flour as the Shirayim. Therefore, it may be returned to the pan and a new Kemitzah may be taken. When, however, the Pesul of the Kemitzah is a weak one, one might have thought that Ben Beseira agrees that the status of the Kemitzah and the status of the Shirayim have been established already, and the invalid Kemitzah may not be returned to the Minchah.
Accordingly, if the Mishnah would have recorded the dispute between Ben Beseira and the Chachamim with regard to all of the Pesulim of Kemitzah, one would have thought that the Machlokes does not apply to the Pesul of performing the Kemitzah with the left hand. Since performing the Kemitzah with the left hand is a weaker Pesul, one would have thought that even Ben Beseira agrees that the status of the Kemitzah and the status of the Shirayim have been established and cannot be changed, and one may not return the Kemitzah to the Minchah and redo it. Therefore, the Mishnah needs to state that even when the Kemitzah is taken with the left hand, Ben Beseira maintains that one may return it to the Minchah and take a new Kemitzah. (Mordechai Zvi Dicker)