1) THE FLOUR BETWEEN THE KOHEN GADOL'S FINGERS
QUESTION: Rebbi Yehoshua ben Uza'ah asked about the status of the flour that gets stuck between the fingers of the Kohen Gadol when he performs Kemitzah (the act of scooping up a handful of flour from the Minchah offering to burn on the Mizbe'ach). Is that flour considered part of the Kometz (which is burned upon the Mizbe'ach) or part of the Shirayim (the leftover flour which is eaten and not burned upon the Mizbe'ach)?
The Gemara relates that Rebbi Yehoshua ben Uza'ah answered his own question after he asked it. He concluded that the status of the flour between the fingers of the Kohen Gadol remains uncertain, a Safek.
What sort of answer is that? When he asked his question in the first place, the status of the flour was also uncertain.
(a) TOSFOS (DH v'Hadar) explains that perhaps at one point Rebbi Yehoshua ben Uza'ah thought that there was an answer to his question and that the flour between the Kohen's fingers was either certainly Kometz or certainly Shirayim. Upon further thought, however, he concluded that no such answer can be given and that his original question remains, and thus the status of the flour remains in doubt.
(b) TOSFOS answers further and says that the original question of Rebbi Yehoshua ben Uza'ah was not whether the flour is considered Kometz or Shirayim. His question was whether the flour that remains between the fingers of the Kohen has the status of flour of Kometz/Shirayim or whether it has the status of a Minchah offering for which Kemitzah was not performed ("Tevel"). The reason why the flour would be considered Tevel even though an act of Kemitzah was performed with it is because flour inside the Kohen's fist is fit to become the flour of Kometz only if the Kohen intends for it to become the Kometz. Since a person normally does not consider the substance between his fingers to be part of what he is holding in his fist, it is possible that the Kohen did not intend to sanctify the flour between his fingers as Kometz and thus it cannot have the Kedushah of Kometz. On the other hand, it cannot be considered Shirayim, because it was actually taken within the fist. For this reason, it should retain its previous status of Tevel -- flour of a Minchah offering for which Kemitzah was not performed.
In summary, there were three possible answers to the question with regard to the status of the flour between the Kohen's fingers. Rebbi Yehoshua ben Uza'ah concluded that the flour cannot be considered Tevel. Rather, it is considered Minchah with which Kemitzah was done, and thus it can be only Kometz or Shirayim.
However, since Rebbi Yehoshua ben Uza'ah concludes that the status of the flour is still in doubt (the doubt being whether it is Kometz flour or Shirayim flour), what practical difference does it make whether the doubt involves two possibilities (Kometz or Shirayim) or whether it involves three possibilities (Kometz, Shirayim, or Tevel)? Tosfos answers that if it is possible that the flour is Tevel, then if it falls into a permitted food it will forbid that food and will not become Batel even if there is a quantity of food many times greater than the flour, because Tevel does not become Batel. If the doubt is only whether the flour is Kometz or Shirayim, then if the flour falls into a permitted food it will be Batel and the food will be permitted.
(c) The RITVA answers that when the Gemara says that Rebbi Yehoshua ben Uza'ah concluded that the status of the flour is a Safek, he concluded that it is definitely not Kometz alone and not Shirayim alone, but rather it consists of both Kometz and Shirayim. The only doubt that remains is the exact point at which the flour between the fingers ceases to be Kometz and begins to be Shirayim. The Ritva compares this doubt to the doubt of Bein ha'Shemashos in Shabbos (33b); Bein ha'Shemashos is part day and part night, but the point during Bein ha'Shemashos that separates between day and night is unknown.
According to the Ritva's explanation, the continuation of the Gemara seems problematic. The Gemara says that the flour left between the Kohen's fingers may not be burned before the Minchah, because "perhaps the flour is Shirayim." Why does the Gemara say "perhaps" it is Shirayim? According to the Ritva, Rebbi Yehoshua ben Uza'ah concluded that it definitely contains Shirayim! Apparently, the Ritva understands that the word "Dilma" ("perhaps") here means "certainly" and not "perhaps," as the Ritva himself indeed explains the meaning of the word elsewhere (Eruvin 3a and 48a).