QUESTION: The Gemara derives from a verse in Iyov (31:20) that the Mitzvah of Reishis ha'Gez applies only to the wool of a lamb.
How can a verse in Iyov teach the meaning of a verse in the Torah? The Gemara in Bava Kama (2b) teaches that "Divrei Torah mi'Divrei Kabalah Lo Yalfinan" -- we do not derive Torah law from the words of the Prophets! (TOSFOS DH Asya)
(a) TOSFOS answers that the Gemara is not teaching an actual Gezeirah Shavah with the verse in Iyov and the verse in the Torah. (A Gezeirah Shavah is a Halachah l'Moshe mi'Sinai, and it obviously cannot be derived from a verse in Kesuvim, which was not yet written at the time the Torah was given.) The Gemara is merely using the verse in Iyov as a "Giluy Milsa" to prove the definition of the word "Gez." (See Insights to Chulin 66:4.)
(b) However, Tosfos points out that the Gemara implies that there is an actual Gezeirah Shavah with the verse in Iyov. (See RASHI to Megilah 2b, DH Perazi Perazi, for another example of a Gezeirah Shavah with a verse in Kesuvim and a verse in the Torah.) Nevertheless, the rule of "Divrei Torah mi'Divrei Kabalah Lo Yalfinan" does not apply here, because the Gezeirah Shavah is not teaching any law that is not written in the Torah itself. By teaching the Gezeirah Shavah, the Gemara teaches that when the Torah writes the word "Gez," it means to limit the laws of Reishis ha'Gez to lamb's wool.


QUESTION: Rav and Shmuel teach that the Rabanan instituted a minimum Shi'ur of one-sixtieth for the three types of Matnos Kehunah for which the Torah gives no minimum Shi'ur: Terumah, Reishis ha'Gez, and Pe'ah.
The Yerushalmi (Bikurim) adds that the Rabanan also instituted this minimum Shi'ur for Bikurim. Chalah, in contrast, has a different Shi'ur, because one generally does not bake enough at one time such that the minimum Shi'ur should be one-sixtieth. Instead, the Rabanan instituted that an ordinary person must give one part of twenty-four, and a professional baker must give one part of forty-eight.
The Gemara questions the teaching of Rav and Shmuel from the Mishnah (Terumos 4:3) that says that the Shi'ur for Terumah of a generous person is one-fortieth. The Gemara concludes that when Rav and Shmuel say that the Shi'ur for Terumah is one-sixtieth, they are referring to the Shi'ur that the Rabanan instituted for one who separates Terumah mid'Rabanan (such as from fruits and vegetables that have no Chiyuv Terumah mid'Oraisa).
This answer is problematic. In the same list, Rav and Shmuel mention that the Shi'ur of Reishis ha'Gez is one-sixtieth. This must be referring to the Rabanan's Shi'ur for the Mitzvah of Reishis ha'Gez mid'Oraisa, since there is no Reishis ha'Gez that is mid'Rabanan. (In Chutz la'Aretz, the obligation is either mid'Oraisa, as Rebbi Elazar maintains, or there is no obligation at all, as Rebbi Ila'i maintains.)
If they are referring to the Mitzvah mid'Oraisa when they mention the Shi'ur of Reishis ha'Gez, then why are they not also referring to the Mitzvah mid'Oraisa when they mention the Shi'ur of Terumah? If, on the other hand, they are discussing entirely different types of Mitzvos -- Terumah mid'Rabanan and Reishis ha'Gez mid'Oraisa, then why do they not give different Shi'urim for different types of people with regard to Reishis ha'Gez? That is, just as that Rabanan gave different Shi'urim for Terumah d'Oraisa (one-fortieth for a generous person, one-fiftieth for an average person, one-sixtieth for a stingy person), the Rabanan should also give different Shi'urim for Reishis ha'Gez mid'Oraisa!
(a) RAV SHLOMO ZALMAN AUERBACH zt'l in MA'ADANEI ARETZ (Terumos 3:1) suggests a reason to differentiate between Terumah and Reishis ha'Gez. For Terumah, the Rabanan gave a fluctuating Shi'ur because the normal manner of separating Terumah is to separate it together with Ma'aser Rishon and Ma'aser Sheni, which do have a set Shi'ur mid'Oraisa. If the Rabanan would have given a set Shi'ur for Terumah d'Oraisa, then one might have thought that the Shi'ur itself is mid'Oraisa, just as it is mid'Oraisa for the other Matanos that are separated from the fruit at the same time. The Rabanan gave Terumah a fluctuating Shi'ur, making it dependent upon the generosity of the giver, in order to make it clear that the Shi'ur is not mid'Oraisa.
There is another difference between the Shi'ur d'Rabanan for Terumah d'Oraisa and the Shi'ur d'Rabanan for Reishis ha'Gez and the other Matanos. Terumah is separated based on an estimation, and thus the exact minimum Shi'ur of one-sixtieth for Terumah might not always be reached. Also, even if one separated less than one-sixtieth, the Terumah is valid b'Di'eved. The reason why the Rabanan did not establish the Shi'ur of one-sixtieth as an exact Shi'ur that is Me'akev is in order to show that mid'Oraisa there is no Shi'ur for Terumah.
In contrast, the other Matanos -- Reishis ha'Gez, Pe'ah, and Chalah -- have a constant, unvarying Shi'ur, since they are not given with other Matanos that have a Shi'ur d'Oraisa.
(b) RAV CHAIM KANIEVSKY shlit'a (in DERECH EMUNAH, Bikurim 10:1) writes that Reishis ha'Gez is not a common Mitzvah, and, therefore, the Rabanan did not establish a larger Shi'ur for a generous person. They established a single Shi'ur -- one-sixtieth -- and one who wants to add to it certainly may do so, and he will merit great blessing. (This approach also may explain why Pe'ah and Bikurim, which are given only once a year, have a fixed Shi'ur.) The Mitzvah of separating Terumah, however, is performed often, whenever one wants to eat his produce. (Mordechai Zvi Dicker)
QUESTION: The Gemara quotes the Mishnah in Pe'ah (1:1) that says that, mid'Oraisa, there is no minimum Shi'ur for the Mitzvah of Bikurim. The Rabanan, however, instituted a minimum Shi'ur of one-sixtieth of one's entire first harvest of any of the seven species (see Yerushalmi Bikurim 3:1; Rambam, Hilchos Bikurim 2:17).
RASHI (DH d'Oraisa) explains that the Mishnah there does not mention Terumah as a Mitzvah for which the Torah gives no minimum Shi'ur, because its Shi'ur is alluded to in the Torah. Is Rashi implying that there is no allusion in the Torah for the Shi'ur of Bikurim?
ANSWER: RAV MENACHEM ELIEZER of Shilishak, in YA'IR KINO to Maseches Kinim (quoted by ALIYOS ELIYAHU, note #107) found an allusion in the Torah to the enactment to give at least one-sixtieth of one's first crops as Bikurim, although it is not as straightforward as the allusion for the Shi'ur of Terumah (and thus the Mishnah mentions Bikurim as a Mitzvah that has no minimum Shi'ur). He explains as follows.
The Torah (Devarim 26:2) says that the fruits of Bikurim should be placed in a "Tene" (a certain type of basket) and brought to Yerushalayim. The BARTENURA (to Tamid 3:6 and Kelim 12:3) points out that a "Tene" holds the volume of half of a Se'ah. This implies that from even the smallest orchard, a half-Se'ah of Bikurim must be set aside.
The Gemara in Kesuvos (111b) teaches that when the Jews fulfill Hash-m's will perfectly, even their poorest vines will produce so many grapes that it will take two donkeys to carry away the yield of each vine (see Maharsha there). We may assume that when the Torah describes the Mitzvah of Bikurim and the requirement to bring the first fruits in a half-Se'ah "Tene," it is referring to the optimum situation in which the people follow the word of Hash-m, when each vine is blessed with two donkey-loads' of produce.
How much can a donkey carry? The Gemara in Bava Metzia (80a) teaches that a donkey can hold up to 15 Se'ah of wheat. The amount that two donkeys can carry, therefore, is 30 Se'ah.
The Mishnah in Bikurim (1:11) teaches that the minimum amount of property that one must own in order to be obligated in the Mitzvah of Bikurim is one tree and its surrounding land. Consequently, the minimum amount of produce from which Bikurim must be separated is one tree's worth of produce. The amount of Bikurim from that produce fits into a half-Se'ah "Tene."
Accordingly, the smallest vineyard from which Bikurim is brought is one vine, and, in the optimal situation, even the worst vine in Eretz Yisrael produces 30 Se'ah of grapes. Since the "Tene" in which the Bikurim must be brought contains half of a Se'ah, which is one-sixtieth of the amount of grapes that the vine produces (30 Se'ah), it emerges that the minimum amount of fruits that must be separated as Bikurim is one-sixtieth of the fruit that is produced! Thus, the Torah indeed alludes to the minimum Shi'ur enacted by the Rabanan.