1) THE MINIMUM SIZE OF A SHOFAR
QUESTION: The Beraisa lists five things that require the measurement of at least one Tefach: a Shilya, a Shofar, the spine (Shidrah) of a Lulav, a wall of a Sukah, and Ezov (hyssop, for the Parah Adumah or a Metzora). Raban Shimon ben Gamliel says that a Shofar must be long enough to be visible from both ends when one wraps his fingers around it.
Why do the Tana'im need to teach two ways of determining the minimum size of the Shofar (a Tefach, and visible at both ends)?
ANSWERS:
(a) The ROSH in Rosh Hashanah (28b) explains that the Chachamim decreed that a Shofar must be a Tefach in order for it to be held by four fingers of a person's hand and yet remain visible on both ends.
There are two approaches to understanding the words of the Rosh. The LEVUSH (OC 586) understands that the Rosh means that the minimum Shi'ur for a Shofar is mid'Rabanan
Others explain that there are situations in which the Torah empowers the Chachamim to determine the specific parameters of the Halachah. For example, the Gemara in Chagigah (18a) teaches that the prohibition of Melachah on Chol ha'Mo'ed is mid'Oraisa, but the Torah empowers the Chachamim to decide what Melachos are included in the prohibition. In the same way, perhaps the Torah empowers the Chachamim to determine the minimum size of a Shofar, and once that Shi'ur is determined, it is mid'Oraisa. The Chachamim decided that the Shi'ur should be a Tefach so that it can be held in four fingers and still be visible.
(b) The RITVA explains that actually two different Shi'urim were given for a Shofar. For small and normal-sized people, the Shofar must be at least one Tefach long. (For exceptionally large people, a Tefach does not suffice, and the Shofar must be large enough to be held in four fingers and still remain visible at both sides.)
2) IS THE "TEFACH" OF THE "SHIDRAH" OF A LULAV A REAL "TEFACH"?
QUESTION: The Beraisa lists five things that require the measurement of at least one Tefach: a Shilya, a Shofar, the spine (Shidrah) of a Lulav, a wall of a Sukah, and Ezov (hyssop, for the Parah Adumah or a Metzora). Rebbi Parnach explains that the length of the Shidrah of a Lulav must be one Tefach greater than the length of the Hadasim (which must be at least three Tefachim) that accompany the Lulav.
TOSFOS (DH Shidrah) asks (in his second question) that Rebbi Parnach's explanation seems to conflict the way the Gemara in Sukah (32b; see Insights there) explains Rebbi Tarfon's explanation of the measurement of the Lulav and Hadasim. The Gemara there explains that Rebbi Tarfon maintains that the Halachah that the Hadasim must be three Tefachim long and the Lulav four Tefachim long is not meant literally. Rather, Rebbi Tarfon is referring to a small-size Tefach. We find that some things are measured with an Amah of five Tefachim, and other things are measured with an Amah of six Tefachim. Similarly, some things are measured with a Tefach from a five-Tefach Amah, and other things are measured with a Tefach from a six-Tefach Amah (that is, a five-Tefach Amah is divided into six parts, and the resulting six parts are small-size Tefachim, each of which is a little more than four-fifths of an ordinary Tefach).
Accordingly, Rebbi Parnach and Rebbi Tarfon do not seem to agree with each other, because Rebbi Tarfon is referring to a much smaller measurement when he discusses the Lulav and Hadasim. Are they indeed arguing?
(a) TOSFOS in Sukah (32b, DH Tzei) says that they indeed are arguing about the minimum length of the Lulav and Hadasim.
(b) TOSFOS here (DH Shidrah Tefach) says that they do not argue. The Beraisa here states merely that there are five things that are measured with a Tefach. This statement does not include the actual size of that Tefach. Accordingly, Rebbi Parnach's statement is not at odds with Rebbi Tarfon's opinion.
(c) Alternatively, Tosfos here answers that the Gemara in Sukah, which is explaining the view of Rebbi Tarfon, maintains that Rebbi Tarfon measured only Hadasim using the small Tefach, but not the Lulav. Accordingly, there is no reason to say that Rebbi Tarfon argues with the explanation of Rebbi Parnach, who refers to the minimum length of the Lulav. (Y. MONTROSE)

26b----------------------------------------26b

3) THE "SHILYA" THAT EMERGES AFTER A BIRTH
QUESTION: The Gemara quotes Rav who says that the first three days after a woman gives birth, we assume that any placenta (Shilya) that comes out of her is part of the first child. After three days, any Shilya that comes out of her is suspected to be from a different child. Rav Kahana questions this ruling of Rav from another statement of Rav, in which Rav said that one child does not wait inside the mother after its sibling has been born, but rather it comes out soon afterwards.
The Gemara concludes that both statements are true. If the first child born is a Nefel (stillborn), we assume that the Shilya that comes out within three days is associated with that child, but after three days it is not associated with that child. If the first child is a healthy child, then the Shilya that comes out even ten days later is assumed to be associated with the first child and is not from another child; this is what Rav means when he says that a child, even a Nefel, does not wait to come out after its sibling is born.
There are a number of Gemaras that seem to contradict this second statement of Rav. The Gemara later (27a) says that Yehudah and Chizkiyah, the sons of Rebbi Chiya, were born three months apart. The Beraisa later (45a) says that a pregnant woman is allowed to use a Moch in order to prevent the child she is carrying from being turned into a Sandal. RASHI there (DH Sandal) explains that a Sandal can occur when a woman becomes pregnant with a second child, and the second child crushes the first, turning him into a Sandal. According to Rav's statement, a woman cannot become pregnant a second time! How does Rav understand these Gemaras? (See Insights to Nidah 25:3.)
ANSWERS:
(a) The RAMBAN and RITVA cite an opinion that says that Rav argues with the Beraisa, and he does not accept the accuracy of the story about Yehudah and Chizkiyah.
Both the Ramban and Ritva disagree with this explanation. They ask that the Halachah in the case of the Moch is an explicit Beraisa, the words of a Tana, with which Rav should not be arguing. Moreover, Yehudah and Chizkiyah were students of Rav, and he presumably knew the truth about their births. Why would the Gemara later (27a) relate something that is not accurate?
(b) The Ramban gives an explanation for the Beraisa similar to that of RABEINU TAM (quoted by TOSFOS to Yevamos 12b, DH Shema), who explains that the concern is that the woman is already carrying twins. Since there is little space in the womb, there is a concern that any seed that enters the womb might crush one of the existing embryos and turn it into a Sandal. That seed itself, however, cannot develop into a child, as the Gemara later (27a) says (a woman cannot become pregnant a second time while already pregnant).
With regard to the statement about the births of Yehudah and Chizkiyah, the Ramban answers that Rav certainly agrees that the story is true. When Rav said that a child does not wait to come out after the first child exits, he was referring to children that emerge from the womb in the same month. In the case of Yehudah and Chizkiyah, who were twins conceived at the same time, one was born after the beginning of the seventh month, and the other needed a full nine months, and thus their births were three months apart.
The RAN explains the position of the Ramban further. The Ran addresses an obvious question on the Ramban's approach. The Ramban maintains that if a child is a Nefel, then it definitely will come out when its sibling is born. If no Nefel came out at that time, then we may assume that a Shilya that comes out later must be assumed to be part of the first child that exited (because if it was a second fetus, it would have come out with the first). However, from the case of Yehudah and Chizkiyah, in which one fetus was ready to be born at the beginning of the seventh month and the other needed three more months to develop, we see that it is possible that after one child is born a second child can wait some time before it is born. Why, then, when a Shilya comes out ten days after the first child, do we assume that it is part of the first child? Perhaps it is a second child! How do we know that the Shilya does not represent another child?
The Ran answers that in any case in which the fetus made it to the seventh month and needed only another three months to finish developing, if the pregnancy results in a miscarriage it would be apparent that there was another child when the Shilya passes, and that the Shilya was from that other child. (Y. MONTROSE)

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