1) BUGS THAT CRAWL AND SNAKES THAT WALK
QUESTION: The Gemara quotes Abaye who states that one who eats a crawling bug (such as an ant) transgresses five prohibitions, and one who eats a flying bug (such as a hornet) transgresses six.
We find an additional prohibition that should apply in each case: "Do not defile your souls... with anything that treads upon the ground (b'Chol Asher Tirmos)" (Vayikra 20:25). Abaye should say that one who eats a crawling bug transgresses six prohibitions, and one who eats a flying bug transgresses seven. Why does he omit the prohibition of defilement?
ANSWERS:
(a) RASHI (DH Tzir'ah) answers that when the verse prohibits creatures that tread (Romes), it refers only to large animals that "tread" upon the ground. Bugs, in contrast, crawl upon the ground (Shoretz). Therefore, the prohibition in this verse does not apply to bugs.
(b) TOSFOS (DH Tzir'ah) cites the Gemara in Sanhedrin (59b) that says that the phrase (Bereishis 1:28), "... uv'Chol Chayah ha'Romeses" -- "And you will rule over the fish of the sea, the birds of the sky, and every wild animal that is Romes*" -- refers to the snake. We see from this that a creature that slithers is also called "Romes." Consequently, the additional verse (in Vayikra 20:25) should also apply to bugs and crawling creatures.
Tosfos answers that there is another reason why that verse does not apply to everything that slithers. The Gemara in Me'ilah (16b) teaches that the verse refers only to the Shemonah Sheratzim, the eight categories of crawling creatures that are Metamei when they are dead.
The RITVA, however, asserts that the question that Tosfos asks on Rashi's explanation has no basis. The verse which Tosfos cites to prove that "Romes" refers to a snake is in the context of the blessing given to Adam ha'Rishon before he sinned. Hash-m told Adam ha'Rishon that he would rule over all of the animals, including the snake, which, as the Gemara in Sanhedrin explains, was supposed to be subservient to man and serve him. At the time of the blessing, the snake had legs and walked. Therefore, Rashi is correct when he says that "Romes" refers only to animals that walk and not to animals that crawl or slither.
Apparently, Tosfos follows his own opinion expressed elsewhere. In Nidah (23a, DH Lisni), Tosfos says that the verse "uv'Chol Chayah ha'Romeses" refers to the snake after it lost its legs. Although the verse discusses the pre-sin snake, it describes the snake as it eventually would look and not as it looked at the time of the blessing (MITZPEH EISAN here, RASHASH in Nidah).
Why does Tosfos interpret the verse in such an unusual way? The RASHASH (in Nidah) explains that Tosfos is bothered by the conclusion of the Gemara in Sanhedrin. The Gemara there says that the words "Chayah ha'Romeses" refer specifically to the snake. "Chayah" certainly means a walking animal. If "Romeses" also means a walking animal, how does the Gemara in Sanhedrin know that the verse refers to a snake and not to all other animals? Tosfos concludes that the word "Romeses" refers not to large animals, but to ones that slither or crawl (as Tosfos asserts here in Eruvin). Accordingly, the verse seems to use contradictory words to refer to a single type of animal -- "Chayah" (walking animal) and "Romeses" (slithering animal). It must be that the verse refers to an animal that both walks (before the sin) and slithers (after the sin). The only animal that fits this description is the snake.
2) PLANTED FOR "YEREK" OR "ZERA"
QUESTION: The Beraisa (end of 28a) states that when one plants Shechalayim and Gargir seeds in order to use the greens (Yerek) of those plants, he must separate Ma'aser from both "the greens and the seeds" that grow. If he plants them in order to use the seeds that they produce, he must separate Ma'aser from both "the seeds and the greens" that grow.
Why does the Gemara differentiate between Shechalayim and Gargir that are planted for their greens and ones that are planted for their seeds, if there is no difference in Halachah? In both cases, one must separate Ma'aser from both the greens and the seeds.
ANSWER: TOSFOS (DH l'Zera) explains that there is a difference between Shechalayim and Gargir planted for their seeds and Shechalayim and Gargir planted for their greens. Intent at the time they were planted is the main factor used to determine the primary produce of the plant (Ikar). Any other product from a plant is considered secondary (Tafel). This rule affects a number of Halachic considerations.
First, the Halachah is that one may not separate Terumah from poor quality produce ("Ra") on behalf of high quality produce ("Yafeh"). In the case of Shechalayim and Gargir, the part of the vegetable for which it was planted is considered the higher quality produce ("Yafeh"), while the other fruit is deemed poorer quality ("Ra"). For example, if one planted these vegetables for their greens, he may not separate the seeds as Terumah on behalf of the greens.
Second, the type of Ma'aser that must be separated from vegetables (greens) is determined by the time at which they are harvested. For example, vegetables harvested before Rosh Hashanah of the third year of the Shemitah cycle are subject to the obligation of Ma'aser Sheni. Vegetables harvested after Rosh Hashanah of the third year are subject to Ma'aser Ani.
In contrast, the type of Ma'aser that must be separated from seeds is determined by the time at which the plant reaches a third of its full growth. Seeds from a plant that reached a third of its growth before Rosh Hashanah of the third year are subject to the obligation of Ma'aser Sheni. Seeds from a plant that has reached a third of its growth after Rosh Hashanah of the third year are subject to the obligation of Ma'aser Ani.
If Shechalayim or Gargir plants grow during the second year but are picked in the third year, which type of Ma'aser must one separate from them? If one planted them for their greens, he must separate Ma'aser Ani. If one planted them for their seeds, he must separate Ma'aser Sheni.

28b----------------------------------------28b

3) SWEET ALMONDS AND BITTER ALMONDS
OPINIONS: The Gemara quotes a Beraisa in which the Tana Kama ruled that bitter almonds are obligated in Ma'aser when they are small. They are exempt from Ma'aser when they are fully grown because they have become bitter and are no longer edible.
Conversely, sweet almonds are obligated in Ma'aser when they are fully grown, and are exempt when they are small.
Rebbi Yishmael b'Rebbi Yosi said in the name of his father, "Zeh v'Zeh Liftor" -- "this and this to exempt," while others quoted him as saying, "Zeh v'Zeh l'Chiyuv" -- "this and this to obligate." The Gemara quotes Rebbi Chanina who ruled like the first version of Rebbi Yishmael's statement.
To what do the words "Zeh v'Zeh" refer?
(a) RASHI in Chulin (25b, DH Zeh v'Zeh) explains that "Zeh v'Zeh Liftor" means that both types of small almonds, bitter and sweet, are exempt from Ma'aser. Similarly, "Zeh v'Zeh l'Chiyuv" means that both types of large almonds, bitter and sweet, are obligated in Ma'aser. Accordingly, when the Gemara in Chulin asks, "What use do these large almonds have?" it refers to the large, bitter almonds.
(b) TOSFOS in Chulin (DH Zeh v'Zeh Liftor) points out several difficulties with Rashi's explanation. First, the Beraisa defines the categories as bitter almonds and sweet almonds, not small and large ones. Presumably, the statement of "Zeh v'Zeh" refers to the two categories mentioned in the earlier part of the Beraisa. Second, according to Rashi, the Gemara in Chulin should have been more specific and asked "what use do large, bitter almonds have?"
Because of these questions, TOSFOS takes a different approach. He says that "Zeh v'Zeh Liftor" means that both large and small bitter almonds are exempt, while "Zeh v'Zeh l'Chiyuv" means that both large and small sweet almonds are obligated. Since there is only one type of large almond (sweet) that is obligated according to the opinion of "Zeh v'Zeh l'Chiyuv," the Gemara's question (what use do large almonds have) can refer only to the large, sweet almond.
It is interesting to note that RASHI here in Eruvin (DH Zeh v'Zeh Liftor) explains the Gemara like Tosfos. (See LEV ARYEH to Chulin 25b for why Rashi explains the Gemara here differently than he does in Chulin.)
The words of the Gemara here are quoted by the BEHAG (see ROSH, Berachos 6:3) when he discusses what blessing one recites when he eats almonds. The Behag understands the Gemara like Tosfos and Rashi here. He rules that we should follow Rebbi Chanina who says "Zeh v'Zeh Liftor," which means that all bitter almonds are exempt from Ma'aser. Further, he writes that one should recite the blessing of "Borei Pri ha'Etz" for a small bitter almond (see Rosh there at length, where he discusses whether the blessing of "Shehakol" should be recited). The BEIS YOSEF (OC 202:5) explains that although the small almonds are bitter, their desirability is their outer skin, which is not bitter when they are small. However, when one eats a large bitter almond, he recites no blessing, because it is more bitter than a small almond, and therefore unfit (and unhealthy) for consumption. This is also the opinion of RABEINU YONAH and the RASHBA in Berachos (36a). (Y. MONTROSE)

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