(Beraisa): One may not buy Terumah with Demei (money paid for produce of) Shemitah, for this limits the time to eat it.

106b - Question (Ravina): If we can learn a Lav from a Kal va'Chomer, why did the Torah write a Lav forbidding Chelev? We could have learned from a Kal va'Chomer from Tahor Sheratzim. They are Chayavei Lavin. All the more so a Lav forbids Chelev, which has Kares!

Answer: We cannot learn from Tahor Sheratzim, for one is liable for any amount.

Question: We could have learned from Shemitah produce!

Answer: We cannot learn from Shemitah, for it forbids anything exchanged for it.

Sukah 35b (Mishnah): One may not use an Esrog of Tahor Terumah for the Mitzvah.

(R. Ami or Rav Asi): This is because he is Machshir it to receive Tum'ah.

(The other of R. Ami and Rav Asi): This is because he wastes Terumah.

They argue about one who made an Esrog Terumah except for the peel. It becomes Huchshar, but Terumah is not wasted.

39a (Mishnah): One who buys a Lulav in Shemitah receives the Esrog for a gift.

Bechoros 12b: Rav Chisda taught that a Shemitah animal is exempt from Bechorah, since Shemitah is for eating, and not for burning (the Eimurim).

Question (Mishnah): One who eats from a Shemitah dough before separating Chalah is Chayav Misah (b'Yedei Shamayim).

If the Chalah were Tamei, we would have to burn it. We should exempt the dough from Chalah, for Shemitah is to be eaten, and not burned!

Answer: "L'Doroseichem" obligates a Shemitah dough in Chalah.

Rambam (Hilchos Shemitah 5:17): One may cut trees in Shemitah for the wood before they have fruits. Once they start to make fruits, one may not cut them, for he wastes the food, and it says about Shemitah "for you to eat", but not to waste.

Rashi (75b DH Shevi'is): The Isur to buy Terumah with Demei Shemitah is because it limits the time to eat Terumah, for one will may not eat it after Bi'ur.

Chazon Ish (Shevi'is 14:13): The Isur is due to wasting Shemitah (if it will become Tamei), and also because it limits the time to eat Terumah. Also the Gra (Shevi'is 8:7) says that the Isur is due to both (and that the Mishnah in Shemitah connotes that it is primarilydue to Shemitah).

Maharit (1:83): People feed strawberry leaves to silkworms. May one do so in Shemitah? Taking the leaves harms human food. One may not cut trees mishe'Yotzi (from when they give out - Shevi'is 4:10). The Rambam and Rashi explain that this is when they produce green leaves, for then we are concerned for wasting the fruit. R. Shimshon says that it is when they produce fruits; he is an individual against them. Feeding the strawberry leaves after Chanatah (budding) overtly harms the fruit. It dries up and falls. Even if the gain of silk is worth more than the loss of fruit, this permits regarding 'Bal Tashchis', but not regarding Kedushah. I permit because these trees are not planted for food or fruits, rather, for silk. Therefore, 'to eat, but not to waste' does not apply. Rather, it is a loss to leave them for fruits!

Maharit: R. Shimshon is correct. Shevi'is 4:10 discusses from when one may cut various kinds of trees; all of them depend on levels of development of the fruits. Rashi retracted (in Berachos 36b, which cites that Mishnah), and the Rambam retracted in the Mishnah Torah. Before it produces fruit, one may cut the tree. Even after it produces fruit, one may cut the leaves, even though it causes the fruits to dry up and fall. This merely causes the food to be ruined; it is not overt. The Yerushalmi permits this. Whatever is not ready to eat, one may benefit from it in a normal way, even if this will prevent being able to eat it later. We expound "for you" - for all your needs. If it is edible, we do not use it for other things. Therefore, one may not cut a tree after it brought fruits.

R. Yom Tov Algazi (on Ramban Hilchos Bechoros/Chalah p.26a DH v'Hinei l'Fi): The Ramban holds that it is a Mitzvas Aseh to eat Shemitah, and not to sell it or waste it. Stam eating is a k'Zayis. Why did the Gemara challenge Rav Chisda from a Mishnah that teaches that Chalah applies to a Shemitah dough? One can separate any amount for Chalah, but the Isur to waste Shemitah is only for a k'Zayis! The Birkei Yosef holds that just like R. Yochanan holds that the Torah forbids Chetzi Shi'ur of Isur, it obligates doing a Mitzvah with Chetzi Shi'ur (e.g. not to waste Shemitah). However, Tosfos and the Ramban hold that less than a Beitzah is not Mekabel Tum'ah mid'Oraisa. If so, there is no reason to exempt Shemitah from Chalah due to Tum'ah, for one can separate less than a Beitzah! The Ramban must have the text of the Rambam, which suggested exempting only because this is like selling (Shemitah to a Kohen). It did not mention that if it becomes Tamei, it must be burned.

Teshuvas Seridei Esh (2:90 p.602): The Gemara never mentions a Mitzvah to eat Shemitah Peros. The Ramban counts this for a Mitzvah, i.e. it is a Lav derived from an Aseh to eat it, and not waste it. However, there is no Aseh to eat it, like the Aseh to eat Kodshim and Terumah. Therefore, there is no source to say that the Shi'ur is a k'Zayis. Rather, one may not waste any amount.

Torah Temimah (Vayikra 25:6 (21)): Rashi explains that the opinion that forbids using an Esrog of Tahor Terumah because he wastes it holds that the peel becomes repulsive through being handled. The same should apply to a Shemitah Esrog, but Sukah 39a connotes that one may use a Shemitah Esrog for the Mitzvah! He answered that since only the peel is ruined, but the fruit can be eaten, the Isur 'to eat, but not to waste' does not apply. Only regarding Terumah one may not waste even the peel.

Rebuttal (Har Tzvi 2:111): There is no source to distinguish Terumah from Shemitah. Pe'as ha'Shulchan (Beis Ridvaz) answers that the opinion that forbids because he wastes Terumah holds that it is mere Gerama (causation). This is forbidden regarding Terumah, for which there is a Chiyuv Shemirah (to guard it). There is no Chiyuv Shemirah regarding Shemitah, so one may cause it to be wasted, like the Maharit says.

Toras ha'Aretz (8:35): In Bechoros, we say that if not for "l'Doroseichem", we would have exempted Shemitah from Chalah, for if it will become Tamei, it must be burned, and the Torah said "to eat", and not to burn. He asked that this is only Gerama. The Torah permits it. Why is a verse needed? He answered that without a verse, we would forbid Gerama. The verse teaches that it is permitted.

Rebuttal (Har Tzvi ibid.): The question was not whether one may make it Chalah, rather, whether it takes effect. It is possible to guard it in Taharah so it will be become Tamei. Without separating Chalah, one may not eat it. Separating Chalah permits eating the rest! Maharit's proof from the Yerushalmi is astounding. It discusses passively allowing a loss. One cannot learn from there to permit an act! He relies on what he said, that the Heter is because the trees were planted for silk, and not for the fruits. He does not permit all Gerama. He agrees that one may not cut trees after they bring fruits that are not ready! Perhaps using an Esrog is considered overtly ruining it. Kapos Temarim connotes like this.

Har Tzvi: Beis Ne'eman says that the peel of an Esrog is less than a k'Zayis. Regarding (guarding) Terumah, the Torah does not mention eating, therefore the Isur to waste it applies to any amount. We learn guarding Shemitah from "Le'echol", therefore, the Shi'ur is a k'Zayis. We are not concerned for wasting less than this. One can challenge this. Teshuvas R. Chaim Rapaport (YD 59) says that the Isur of Shemitah applies to any amount. If so, why may one use an Esrog of Shemitah? However, I proved that the Isur does not apply to any amount. If one must eat Isur (due to Piku'ach Nefesh), he eats the lightest Isur. Shemitah is lighter than than Tevel (Yoma 83a). The Ran asked why we slaughter on Shabbos for a Choleh. He should rather eat Neveilah, which is a light Isur compared to Melachah on Shabbos, which is punishable by stoning! The Ran answers that there is a stringency to Neveilah, that he transgresses for every k'Zayis. Therefore, if one were liable for any amount of Shemitah, it would be more stringent than Tevel. Rather, also the Shi'ur for Shemitah is k'Zayis. Also, in Zevachim we say that any amount of Sheratzim is forbidden, but we do not say so about Shemitah. What was the question about Chalah from a dough of Shemitah? Some Poskim obligate Chalah from a dough kneaded with fruit juice, even though it is not Mekabel Tum'ah! Rather, Rav Chisda holds that Kedushas Shevi'is overrides Bechorah and anything that might contradict Kedushas Shevi'is. Therefore, it should override Chalah, lest a dough be Huchshar (and become Tamei), and perhaps it will be a k'Zayis or it will join with another partial Shi'ur to a full k'Zayis. I can answer that we are not concerned for wasting an Esrog. Stam Esrogim are planted for the Mitzvah with intent that the peel will be ruined, so there is no Isur to ruin it.

Suggestion (the questioner in Tzitz Eliezer 6:33:7): Sidur Ya'avetz (p.101, Hilchos Milah 76) brings a custom after sucking the blood from the Bris, to put wine in the mouth and spit it all out on the Milah for Refu'ah. Even though the Yerushalmi forbids using wine for Refu'ah, perhaps the Isur to waste Shemitah does not apply to Chetzi Shi'ur. Beis Ridvaz concludes that it is Asur. Mishmeres ha'Bayis says that the Yerushalmi permits. We may rely on this for the above Refu'ah.

Rebuttal (Tzitz Eliezer): Mishmeres ha'Bayis said that it is only a partial proof from the Yerushalmi (one can explain it differently), and surely there is an Isur mid'Rabanan. The Yerushalmi discusses whether the Torah forbids any amount. Toras ha'Aretz and Bayis Ne'eman concluded that the Isur applies to Chetzi Shi'ur. Shabbos ha'Aretz says not to fill a cup for Havdalah with Shemitah wine to overflowing for a Siman Berachah, since what spills is wasted, and not to use Shemitah wine for the second cup at the Seder, from which we spill drops (for the plagues and their initials), He forbids even less than a Shi'ur which is a Siman Berachah and a custom of Yisrael. He also brings a proof from Zevachim 75b (which Stam forbids buying Terumah with Demei Shemitah. It did not give a Shi'ur.) If the above Refu'ah were a Mitzvah, perhaps there would be room to permit (but it is not). Sefer ha'Shemitah and Tzitz ha'Kodesh were lenient to use a Shemitah Esrog when no other was available. Toras ha'Aretz is stringent about this