1) RECITING A BLESSING FOR RICE LIKE "MA'ASEH KEDEIRAH"
QUESTION: The Gemara attempts to prove that rice requires the blessings "Borei Minei Mezonos" and "Al ha'Michyah" from a Beraisa that states, "One recites a blessing [on rice-bread or millet-bread] before eating and after eating, just like Ma'aseh Kedeirah (a dish of cooked grain made from one of the five species of grain)." The Gemara concludes that this does not mean that we recite the same blessing for rice as we do for Ma'aseh Kedeirah. Rather, the Beraisa is teaching that just as Ma'aseh Kedeirah requires a blessing before and after it is eaten ("Borei Minei Mezonos" and "Al ha'Michyah"), so, too, do rice and millet ("sheha'Kol" and "Borei Nefashos").
Why does the Beraisa compare rice to Ma'aseh Kedeirah just to teach that rice requires a blessing both before and after it is eaten? The Beraisa could compare rice to any food, because any food requires a blessing before and after it is eaten!
ANSWERS:
(a) The PNEI YEHOSHUA answers that the Beraisa is not teaching what the blessing for rice is, but rather what it is not. Rice bread is not afforded any special status, and its blessing is not ha'Motzi. The blessing on rice remains Borei Minei Mezonos, even when it is baked into bread. (The TZELACH suggests a similar approach.)
(b) The MAGID TA'ALUMAH explains that just as a small amount of Ma'aseh Kedeirah joins with any other food to make the proper Shi'ur upon which one must recite a Berachah Acharonah, so, too, rice joins with any other food to complete a Shi'ur that obligates one to recite a Berachah Acharonah.
(c) The SEFER BEIS YOSEF explains that the Gemara later in Berachos (44a) quotes an opinion that one does not recite a Berachah Acharonah after drinking water or eating vegetables. To distinguish rice from water and vegetables according to this opinion, the Beraisa compares it to Ma'aseh Kedeirah.
2) RABAN GAMLIEL'S PERPETUAL CYCLE OF BLESSINGS
QUESTION: Raban Gamliel maintains that one recites the full Birkas ha'Mazon after eating any of the seven species of fruits. One of those species is the fruit of the vine. Hence, Raban Gamliel would require one to recite the entire Birkas ha'Mazon after drinking a cup of wine. Since Birkas ha'Mazon must be recited over a cup of wine, one would be caught in an endless cycle of blessings! How can Raban Gamliel maintain that one must recite Birkas ha'Mazon over the fruits of the seven species?
ANSWER: TOSFOS (DH Nasan Raban Gamliel) explains that when a person drinks only a Melo Lugmav (a cheek-full) of wine, he is not required to recite Birkas ha'Mazon according to Raban Gamliel. "Al ha'Michyah" suffices. Raban Gamliel requires one to recite Birkas ha'Mazon only after he drinks a full cup of wine, which is considered "sitting down to drink wine."

37b----------------------------------------37b

3) WHEN DOES ONE BLESS "SHEHECHEYANU" WHEN OFFERING A "KORBAN MINCHAH"?
OPINIONS: The Gemara cites a Beraisa that says that when a person brings a Minchah offering, he should recite the blessing of "Shehecheyanu." Under what circumstances does this apply?
(a) RASHI in Menachos (75b, DH Hayah Omed u'Makriv Menachos) explains that a Kohen who offers a Korban Minchah on the Mizbe'ach for the first time in his life recites the blessing of Shehecheyanu.
According to TOSFOS' text of Rashi, the words of Rashi read "for the first time this year."
(b) RASHI there suggests another explanation. When a type of Minchah is brought for the first time (such as the Minchas ha'Omer, which is the first to be brought from the new year's produce), the Kohen recites Shehecheyanu.
(c) The ROSH and RABEINU YEHUDAH HA'CHASID write that any time a Kohen offers a Minchah offering on the Mizbe'ach, he recites Shehecheyanu.
(d) RASHI here (DH Hayah, and DH Omer Baruch Shehecheyanu) and RABEINU SHEMAYAH (quoted by Rabeinu Yehudah ha'Chasid) say that any person, even a Yisrael, who brings a Minchah offering a protracted period from the last time he brought one recites Shehecheyanu. Rabeinu Shemayah adds that it is uncommon to bring a freewill Minchah offering, and therefore one recites Shehecheyanu every time it is brought.
TOSFOS here (DH Hayah) says that this explanation is problematic, because the Beraisa clearly says, "Hayah Omed u'Makriv Menachos b'Yerushalayim, Omer" -- "one who was standing and offering Menachos in Yerushalayim says...." This clearly indicates that the one who actually offers the Minchah is the one who says the blessing. This cannot refer to a Yisrael, who may not actually offer a Minchah on the Mizbe'ach.
Tosfos also says that this explanation does not fit the Beraisa's statement that "he took them to eat them." A Yisrael is not allowed to eat a Minchah. How, then, can the Beraisa be discussing a Yisrael?
The YA'AVETZ answers that Rashi was bothered by a different part of the text of the Beraisa. The Beraisa refers to a person who was "standing and offering Menachos in Yerushalayim." Why does the Beraisa add that he was in Yerushalayim? It is obvious that he was in Yerushalayim, since all Korbanos are brought only in the Beis ha'Mikdash in Yerushalayim!
Rashi understood from the words "in Yerushalayim" that the Beraisa is referring to all of Yerushalayim, and not merely to the specific area of the Beis ha'Mikdash. This is why Rashi understood that the Beraisa is referring to a Yisrael who is bringing a Minchah in Yerushalayim. The Yisrael is not actually offering it on the Mizbe'ach.
While the Ya'avetz does not address the second question of Tosfos, we may suggest that Rashi understood that the text "he took them to eat them" is not referring to the Yisrael who brought the Minchah, but to a Halachah involving the Kohen.
(e) Another version of RASHI in Berachos (according to the reading of the TOSFOS HA'ROSH) explains that a Yisrael who offers a Minchah for the first time in his life recites Shehecheyanu.
(f) Tosfos says that the Kohen who brings the first Minchah of his Mishmar recites Shehecheyanu, because each Mishmar serves only once every half a year.
The Ya'avetz in Berachos comments that Tosfos' statement implies that one can say Shehecheyanu on events that occur biannually. The BEIS YOSEF (OC 225) discusses this point at length and is uncertain whether one recites Shehecheyanu on events which occur annually or even on events that occur biannually. He discusses whether or not one should say Shehecheyanu every six months on a new fruit that grows during two seasons a year.
It is possible that Rashi did not give this explanation because he maintained that one cannot say Shehecheyanu on a biannual event.
4) CRUMBS THAT CAME FROM A LOAF OF BREAD
OPINIONS: The Gemara says that the blessing "ha'Motzi" is recited on pieces of bread larger than a k'Zayis. If the pieces of bread "came from a large piece of bread (Lechem Gadol)," then one recites "ha'Motzi" even on those pieces. What does it mean that the pieces come from a "large piece of bread"? The crumbs of a Minchah offering always come from a large piece of bread, and yet the Gemara says that one does not recite "ha'Motzi" if he eats crumbs of a Minchah that are less than a k'Zayis.
(a) RASHI here (DH Hacha b'Mai Askinan) explains that when the bread from which the crumbs came still remains and has not been completely crumbled, then the crumbs also have a special status of "bread" and one recites "ha'Motzi" even on the crumbs. Rashi's words imply that it depends on whether the remainder of the loaf is nearby at the time that its crumbs are eaten.
(b) However, RASHI (Kesav Yad) in Menachos (75b) explains that when crumbs are broken off a piece of bread which is larger than a k'Zayis, the crumbs are granted special status because of the size of the remainder of the loaf ("Agav Avihem"), and they require the blessing of "ha'Motzi." This implies that the blessing for crumbs is "Mezonos" only when the entire loaf of bread is crumbled all at once. Rashi in our Sugya probably intends to say the same thing as he says in Menachos.
(c) The RITVA explains that when one bakes the crumbs into one piece of bread but can still see the crumbs that comprise the bread, he recites "ha'Motzi" (even though the individual crumbs are less than a k'Zayis).

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