1) WHEN IS "HEFKER" OBLIGATED IN "MATNOS ANIYIM"?
QUESTION: The Gemara quotes a Beraisa that says that if one is Mafkir his field and then harvests it early the next morning, he is obligated to give Matnos Aniyim (Peret, Olelos, Shikechah, Pe'ah) from the produce, but he is not obligated to separate Ma'aseros.
Hefker is generally exempt from both Matnos Aniyim and from Ma'aseros. Why, in this case, is the field obligated in Matnos Aniyim?
ANSWERS:
(a) RASHI (DH Ta Shema) explains that only produce that is "fully" Hefker is exempt from Matnos Aniyim. In the case of the Beraisa, the field is not fully Hefker and thus it remains obligated in Matnos Aniyim. (See also Rashi to Temurah 6a, DH Chayav.)
In what way is the field not "fully" Hefker? How can a field be only partially Hefker?
Perhaps Rashi means that the field is not fully Hefker because the owner did not declare it Hefker in front of three people (as required by the Gemara in Nedarim 45b). Since the owner did not make it Hefker in a public manner, there is circumstantial evidence that he made it Hefker half-heartedly. Also, the fact that the owner harvested the fruits early the next morning certainly suggests that he did not really want it to be Hefker. (M. KORNFELD)
(b) TOSFOS in Bava Kama (28a, DH Zeh) and Temurah (6a, DH ha'Mafkir) explains that a field is exempt from Matnos Aniyim only while it is Hefker. The fact that a field was once Hefker does not remove the obligation of Matnos Aniyim from it. In contrast, the obligation to separate Ma'aser from a field depends on whether the field was once Hefker. A field that was once Hefker remains exempt from Ma'aser even when someone takes possession of it.
Accordingly, Rashi and Tosfos have two different ways of understanding the Beraisa. Rashi understands that the Beraisa is discussing a person who was Mafkir his field and did not reclaim it before he harvested the field (and thus he harvested the fruits of a Hefker field). According to Tosfos, the Beraisa is discussing a person who was Mafkir his field and did reclaim it before he harvested the produce the following morning.
2) RAV ASHI CHALLENGED RAVA
QUESTION: Rebbi Yochanan (50a) rules that when one sows "Ulshin" (herbs) with intent to use what grows as animal fodder, and he later decides to use the herbs as food for people, the herbs are not fit to be Mekabel Tum'ah unless he has intent (Machshavah) after he picks them from the ground to use them as food for people. The Machshavah that he has when they are in the ground does not suffice to give them the status of human food to be able to be Mekabel Tum'ah.
Rava here says that Rebbi Yochanan nevertheless agrees with regard to Ma'aser that the Machshavah that one has when the herbs are in the ground does give them the status of food to make them obligated in Ma'aseros.
Rav Ashi challenges Rava's statement from the Mishnah earlier (50a) that says that anything that is obligated in Ma'aseros can become Tamei with Tum'as Ochlin. According to Rava, however, the Mishnah's statement is not accurate, because if one had Machshavah that something be food for people when it was in the ground, then the food becomes obligated in Ma'aseros even though his Machshavah does not make it a food with regard to Tum'ah.
RASHI (DH Mesiv) writes that Rav Ashi challenged "l'Rava," to Rava. What is Rashi adding with this short comment? It is obvious that Rav Ashi is challenging Rava's opinion. Rashi cannot mean that Rav Ashi asked his question directly to Rava, because the Gemara in Kidushin (72b) says that when Rava died, Rav Ashi was born, and it learns from there that Hash-m does not let a Tzadik depart from this world until another Tzadik is born to take his place.
Also, the Gemara quotes Rava's response to Rav Ashi's question. How could Rava respond directly to Rav Ashi's question if Rav Ashi was not yet born?
ANSWERS:
(a) The RASHASH answers based on the words of TOSFOS in Chulin (2b, DH Ana), who says that the questions that were asked in later generations were already asked in prior generations. Accordingly, when the Gemara says that Rava answered Rav Ashi's question, it means that the question that Rav Ashi asked had already been posed in the times of Rava, and Rava had answered it then.
(b) The CHOCHMAS BETZALEL and the MELO HA'RO'IM answer that Rav Ashi in fact asked this question personally to Rava. This is consistent with the RAMBAM's statement (in his introduction to Mishneh Torah) that Rav Ashi was a student of Rava, in contrast to the statement of the Gemara in Kidushin.
Indeed, the MAHARAV RENSBURG (by the same author as the Chochmas Betzalel) in Kidushin cites the HILCHOS OLAM who writes that the Rambam's text in Kidushin read, "Before Rava died, Rav Ashi was born." The Gemara means that before one Tzadik (Rava) passed away, another Tzadik was already worthy to take his place. This is consistent with what the Gemara there derives from the verse, "And the sun shines, and the sun sets" (Koheles 1:5). The Gemara says that this refers to the "sun" of Eli ha'Kohen: before it set, the sun of Shmuel, the new leader, was already shining. Just as Shmuel ha'Navi was Eli's disciple for forty years, Rav Ashi was Rava's disciple. Accordingly, Rav Ashi certainly could have asked his question to Rava in person. (D. BLOOM)

51b----------------------------------------51b

3) WHAT IS "BI'UR"?
OPINIONS: The Mishnah teaches that the laws of Shevi'is apply to any produce to which the laws of Bi'ur apply, but there are some types of produce to which the laws of Shevi'is apply but the laws of Bi'ur do not apply. The laws of Bi'ur require that in the Shemitah year, after the time that a fruit is no longer available in the field, one must be Meva'er (destroy) that fruit.
What constitutes Bi'ur?
(a) The RAMBAM (Hilchos Shemitah 7:1-3) explains that Bi'ur means that the produce becomes prohibited to be eaten and it must be burned or destroyed (or eaten before the time of Bi'ur arrives). (The Rambam understands that the meaning of "Bi'ur" in this context is similar to the meaning of "Bi'ur Chametz," the destruction of Chametz.)
This also seems to be the view of RASHI here (DH Kol she'Yesh Lo), who says that Bi'ur means to remove the fruit from one's home. Rashi elsewhere (Pesachim 52b) says that the fruit must be destroyed such as by being placed in an open area where it will be trampled by animals. (See also Rashi to Bava Kama 101b and Yevamos 122a.)
(b) TOSFOS in Pesachim (52b, DH Misba'arin), the RAMBAN (Vayikra 25:7), and the RASH (Shevi'is 9:8) explain that there is no requirement to burn or destroy produce of Shemitah at the time of Bi'ur. Rather, one simply must be Mafkir the produce so that anyone may take it. Once the produce has been made Hefker, even the owner may reclaim it for himself and eat it for as long as he wants. The Ramban proves this from the Tosefta (Shevi'is 8:4) that states that at the time of Bi'ur, a person must take the Shevi'is fruit into the street and make it Hefker so that anyone may take it, and afterwards he may bring it back into his home and eat it until it is finished. This implies that Bi'ur means simply taking the fruit out of one's home and making it Hefker (similar to "Bi'ur Ma'aseros" done in the fourth and seven years). The Ramban cites further support for this explanation of Bi'ur from the fact that produce of Shemitah does not appear in the Mishnah's list in the end of Temurah of Isurei Hana'ah that are either buried or burned.
(c) The RA'AVAD (Hilchos Shemitah 7:3) writes that Bi'ur involves elements of both of the abovementioned opinions. There are two different types of Bi'ur that must be done with fruits of Shevi'is. When fruit of Shevi'is is no longer available in one particular city or location, a person living in that location must be Mafkir the fruit that is in his possession, or he must bring it to Beis Din to distribute. However, when a particular fruit is no longer available in any of the three regions of Eretz Yisrael (Yehudah, Galil, and Ever ha'Yarden -- see Shevi'is 9:2), the fruit must be destroyed.
HALACHAH: The CHAZON ISH rules that today we may be lenient and conduct ourselves according to the RAMBAN, since the laws of Shevi'is today are only mid'Rabanan. (See also Insights to Bava Kama 101:2.)
4) THE HORNS OF A NON-KOSHER ANIMAL
QUESTION: The Mishnah states that all animals that have horns also have hooves, but there are some animals that have hooves but not horns. RASHI (DH Yesh) explains that "hooves" here refer to cloven hooves (a sign of a Kosher animal), because only a Kosher animal (Behemah or Chayah) possesses horns. Therefore, if we know that the species has horns, we know that it also must have cloven hooves (and is Kosher). Rashi (DH v'Yesh) adds, however, that there are certain species, such as swine, that possess cloven hooves but have no horns and therefore are not Kosher.
The Mishnah seems to contradict a statement of the RAN in Rosh Hashanah (6a of the pages of the Rif). The Mishnah in Rosh Hashanah (26a) teaches that all types of Shofar are fit for the Mitzvah of Teki'as Shofar on Rosh Hashanah, with the exception of the horn of a cow, because the horn of a cow is called a "Keren" and not a "Shofar." The Ran there writes that it is possible that the Mishnah is discussing only the horns of Kosher animals. The horn of any non-Kosher animal should be unfit to be used as a Shofar. The Gemara in Shabbos (108a) says that only things that come from a Kosher animal are fit for "the work of Heaven" ("Meleches Shamayim"), which includes the blowing of the Shofar on Rosh Hashanah. (See also Shabbos 108a with regard to the type of parchment on which Tefilin must be written.) The Ran's opinion is cited by the REMA (OC 586:1), who rules that a Shofar made from the horn of a non-Kosher animal is unfit for the Mitzvah on Rosh Hashanah.
How is it possible to have a Shofar from a non-Kosher animal? The Mishnah here states that if the species possesses horns, then it also must possess cloven hooves, and thus it is a Kosher species!
ANSWERS:
(a) The BE'ER HA'GOLAH (OC 586:5) answers that the non-Kosher animal whose Shofar the Ran is discussing is an animal that possesses the signs of a Kosher animal, including horns, but whose mother is not a Kosher species of animal (that is, the offspring is a crossbreed). Since the mother is not Kosher, the child is also not Kosher, as the Mishnah in Bechoros (5b) teaches.
(b) The MAGEN AVRAHAM (OC 586:3) answers based on the Gemara in Chulin (59b). The Gemara there explains that it is necessary to be familiar with the Simanim of a Chayah (undomesticated animal), as listed in the Mishnah there (59a), in order to permit the Chelev of a Chayah to be eaten. (If the animal is a Behemah, its Chelev is forbidden, while if the animal is a Chayah, its Chelev is permitted.) The LEVUSHEI SERAD (on the Magen Avraham) explains that horns on a Chayah is proof that the Chayah is Kosher, because no non-Kosher Chayah has horns. Horns are also an effective way to distinguish between a Chayah and a Behemah, because a Chayah can be identified by its horns that are "Mefutzalos" (see SHULCHAN ARUCH YD 80:1, and Insights to Chulin 59:9), a characteristic which only the horns of a Chayah possess. However, a non-Kosher Behemah can also possess horns, with the exception of swine, which do not possess horns.
Accordingly, the Ran is referring to the horn of a non-Kosher animal, other than swine, which is unfit for use as a Shofar (and is not Mefutzalos, because if it is Mefutzalos, then the animal would be classified as a Chayah and be considered Kosher). The Mishnah -- which states that all animals that possess horns are Kosher -- is referring only to types of Chayah.
(See the PRI MEGADIM on the Magen Avraham, who points out that the above explanation is not consistent with the words of Rashi in the Mishnah here, because Rashi says that only a Kosher Behemah or Chayah possesses horns. Nevertheless, the Magen Avraham may be understood according to the words of the RAMBAM here in Perush ha'Mishnayos. The Rambam writes that the first part of the Mishnah, which discusses the Simanim of fish (Kaskeses and Senapir), is necessary in order to teach which fish is Kosher and which fish is not Kosher. The Rambam also writes that the Mishnah is necessary in order to teach how to discern between a Behemah and a Chayah. The Rambam seems to be referring to the second part of the Mishnah, which discusses horns and hooves, and he is consistent with the explanation of the Magen Avraham, who says that the horns distinguish between a Chayah and Behemah, and not between Kosher and non-Kosher species, because non-Kosher Behemos also possess horns.) (D. BLOOM)
5) RECITING A BLESSING AFTER PERFORMING A MITZVAH
OPINIONS: The Gemara relates that in Ma'arava (Eretz Yisrael), the Jews would recite a blessing after performing a Mitzvah, such as upon removing their Tefilin at the end of the day. After which Mitzvos did the Jews recite a blessing?
(a) RABEINU TAM (cited by TOSFOS here, DH veli'Venei) explains that in Ma'arava they recited a blessing only when they removed their Tefilin before nightfall, since the verse "v'Shamarta Es ha'Chukah" forbids wearing Tefilin at night. They did not recite a blessing after they completed any other Mitzvah or after removing their Tefilin in the morning, since the Torah does not call such acts "Chukah."
If they did not recite a blessing after any other Mitzvah, then why does the Gemara conclude that the ruling of the Mishnah (that a Berachah Rishonah is sometimes recited without a Berachah Acharonah) is said regarding fragrances? The Gemara could have answered simply that the Mishnah is referring to all Mitzvos aside from Tefilin! Rabeinu Tam answers that the Gemara indeed could have explained that the Mishnah is referring to all other Mitzvos.
(b) The RASHBA and RITVA here reject Rabeinu Tam's ruling. They explain that in Ma'arava, they recited blessings after all Mitzvos that have clearly-defined ending points (either because the Mitzvah has been completed, such as Lulav or Shofar, or because the obligation ceases to apply, such as Tefilin or Tzitzis at night).
The ROKE'ACH explains that they recited the blessing of "Lishmor Chukav" after they completed any Mitzvah, based on the verse, "u'Shemartem Es Chukosai" (Vayikra 18:5).
(c) The Ritva also explains that in Ma'arava a blessing was recited after every Mitzvah, but only after they removed their Tefilin did they recite the blessing of "Lishmor Chukav," based on the verse "v'Shamarta Es ha'*Chukah*." After they completed other Mitzvos they recited "Lishmor Mitzvosav."
HALACHAH: The TUR (OC 29) quotes RAV HAI GA'ON who rules that a person may recite a blessing when he removes his Tefilin at the end of the day. The TUR disagrees and asserts that since there is no obligation to recite such a blessing, it is a Berachah l'Vatalah.

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