OPINIONS: The Mishnah says that when one finds an instrument called a "Meritzah," he must assume that it is Tamei because it is used for burying the dead. What is a Meritzah?
(a) The Gemara (21b) explains that it is a tool that crushes stones. Grave-diggers use it when they dig a grave.
(b) The RAMBAM (Perush ha'Mishnayos, cited by the TIKLIN CHADTIN) apparently has a different text in the Gemara. According to his text, a Meritzah is used to crush bones in order to facilitate transporting them to the burial grounds. Bones occasionally need to be placed into a smaller sack when they are transported, and thus they are crushed.
How can the Rambam suggest that a Meritzah is used to crush the bones of the dead? The Halachah clearly forbids breaking or dismembering the bones of the dead in any way (SHULCHAN ARUCH YD 403:6). (TIFERES YISRAEL, HAGAHOS RADAL)
The PEIROS TE'ENAH cites the RADVAZ (Teshuvah #611) who was asked whether one may dismember the body of the dead or break bones in order to transport the body to Eretz Yisrael. He proves that it is permitted from the words of the Rambam here. He explains that in the case that the Rambam describes, the dead body needs to be transported in order to be buried near family members, which is a form of honoring the dead. The bones may be broken in order to enable the body to be transported, since it is done in order to give honor to the deceased. Similarly, transporting a body to Eretz Yisrael is a form of honoring the deceased. Therefore, the bones may be broken in order to enable the body to be transported.
OPINIONS: The Mishnah says that if a Kupitz was found tied to a knife, it has the same status as the knife. The Gemara cites a Beraisa which states that "the knife tied to it has the same status as it has."
In the Beraisa's case, to what is the knife tied? What point does the Beraisa intend to teach?
(a) The TIKLIN CHADTIN explains that the Beraisa refers to a knife tied to a Kupitz. It rules that a knife tied to a Kupitz is judged stringently and is considered like the Kupitz, and thus it must be immersed in a Mikvah before it may be used.
The Mishnah, though, says that if it (i.e. a Kupitz) is tied to a knife, the Kupitz is judged like the knife. The Tiklin Chadtin explains that the Beraisa argues with the Mishnah.
(b) The RAMBAM (Perush ha'Mishnayos) explains that the end of the Mishnah, which says, "If it was found tied to a knife, it has the status of the knife," does not refer to Erev Pesach. Rather, it refers to any time of the year. The Mishnah teaches that when one has a particular knife that he knows is Tahor or Tamei, and later he finds a second knife tied to it, he may assume that the second knife has the same status as the first (and that is why someone tied the two knives together).
This is also the intention of the Beraisa cited by the Gemara. The Beraisa is not discussing a knife tied to a Kupitz, but rather a knife tied to another knife. (KORBAN HA'EDAH)
QUESTION: The Mishnah states that the Paroches needed 300 Kohanim to hold it and immerse it in a Mikvah. The Gemara says that the Mishnah's statement is an exaggeration.
The Chachamim always take great care to show that every word of the Mishnah is meticulously chosen. Why does the Gemara here say that the Mishnah's words are an exaggeration?
ANSWER: The VILNA GA'ON (Kol Eliyahu, Parshas Terumah; see also TIFERES YISRAEL here) offers an ingenious explanation to explain why the Mishnah says that 300 Kohanim were needed to immerse the Paroches. The Vilna Ga'on demonstrates that this number was not chosen at random.
The Mishnah in Tamid teaches that the Paroches was 40 Amos long and 20 Amos wide. Since the Amos used in the measurements of the Beis ha'Mikdash consisted of five handbreadths each (Kelim 17:10), the perimeter of the Paroches was 120 Amos (2 X (40 + 20)), or 600 handbreadths. Therefore, if as many Kohanim as physically possible would participate in the Mitzvah of immersing the Paroches, there would be room for exactly 300 Kohanim to grasp it, since each Kohen would hold two handbreadths of the perimeter with his two hands!
Why, then, does the Gemara say that the number 300 is an exaggeration? The answer is that although it was theoretically possible for 300 Kohanim to grasp the Paroches, it was never actually handled by this number of people. It would have been unusual for the Kohanim's hands to be so closely spaced as to allow them to cover every centimeter of the perimeter of the Paroches. Nevertheless, it is clear that the Mishnah did not choose the number 300 as its "exaggerated" figure randomly. This number was chosen because it represents the theoretical maximum number of Kohanim who could participate in this Mitzvah.
The YEFEH EINAYIM in Tamid, however, raises a serious objection to the calculation of the Vilna Ga'on. According to the Mishnah in Kelim (17:10) and the Gemara in Menachos (97b), the special five-handbreadth Amah measurement that was used in the Beis ha'Mikdash was used only for the manufacture of the movable articles of the Beis ha'Mikdash, such as the Aron, Shulchan, and Mizbe'ach ha'Zahav. For the construction of the actual edifice of the Beis ha'Mikdash, the regular, six-handbreadth Amah measurement was used. (This is the opinion of Rebbi Yehudah. Rebbi Meir maintains that the six-handbreadth Amah was used in an even more limited capacity.) Accordingly, the measurements of the Paroches -- which extended across the entire width of the Heichal in order to enclose the Kodesh ha'Kodashim (or to shield the entrance to the Ulam) -- would have to be measured with the same Amah that was used for measuring the sanctuary itself, or the six-handbreadth Amah. The perimeter of the Paroches would then measure 720, and not 600, handbreadths!
To answer this question on the Vilna Ga'on's explanation, we may suggest that when the Kohanim would grasp the Paroches in order to immerse it, they would not hold it on all four sides. One side had to be left free in order to allow it to be lowered into the Mikvah. If the Kohanim would have grasped the Paroches on the three sides that measured 40, 40, and 20 Amos, and they left the other side (20 Amos) free, then they would have covered 100 Amos, or 600 handbreadths, of the perimeter. (It is likely that this was the actual explanation that the Vilna Ga'on gave, and not as recorded in Kol Eliyahu.) (M. Kornfeld)
(The Chachamim use similar "exaggerations" in Tamid (29a) and Midos (3:8). See Insights to Tamid 29:2 and Chulin 90:3 for explanations of those statements.)