1) GUARDING THE HOLY
OPINIONS: The Mishnah discusses the Mitzvah of Shemiras ha'Mikdash, guarding the Beis ha'Mikdash.
The Rishonim discuss why the Torah requires that the Beis ha'Mikdash be guarded.
(a) The RAMBAM (Hilchos Beis ha'Bechirah 8:1) rules that the purpose of the guarding is not in order to protect the Beis ha'Mikdash from thieves or adversaries. Rather, the Shemirah is a sign of honor and respect for the Beis ha'Mikdash; a palace without guards is not regarded with the same reverence as a palace with guards. Similarly, the ROSH (25b, DH b'Sheloshah) explains that the Shemirah is a sign of respect for the Beis ha'Mikdash, since it shows that the people constantly attend to the Beis ha'Mikdash, even at night.
(b) The MEFARESH (DH b'Sheloshah) writes that the Mitzvah of guarding the Beis ha'Mikdash is a Gezeiras ha'Kasuv. His intention might be what the VILNA GA'ON (1:1) writes explicitly: the Shemirah of the Beis ha'Mikdash is in order to keep out any person who is forbidden to enter the Beis ha'Mikdash, such as one who is Tamei, as the Torah states, "You (Aharon) and your children and your family will be responsible to prevent people from sinning in the Mikdash (by entering it while Tamei)" (Bamidbar 18:1). As the Vilna Ga'on points out, RASHI on the Chumash (Bamidbar 3:6, 18:1) appears to take this approach.
It appears that these two different approaches have different Halachic consequences as well.
1. The AVNEI NEZER (YD 489) explains that there is a practical difference between these two reasons with regard to the obligation of Shemirah during the time that the Beis ha'Mikdash is not standing, such as today. According to the Rambam and other Rishonim who learn that the obligation to guard is in order to show respect to the Beis ha'Mikdash, there is no obligation to perform Shemirah today, since, b'Avonoseinu ha'Rabim, there is no Beis ha'Mikdash to which to show respect.
In contrast, according to Rashi and the Vilna Ga'on, who explain that the purpose of the Mitzvah to guard the Mikdash is in order to prevent people from entering a place which they are not allowed to enter, the Mitzvah still should apply today, since the Kedushah of the Beis ha'Mikdash is still present in the place where the Beis ha'Mikdash stood, and there is still a need to prevent people from going there.
(It may be argued, however, that according to Rashi and the Vilna Ga'on, Shemirah was not meant only to prevent people from sinning, but also to prevent the Beis ha'Mikdash from becoming defiled by sinners, as the verses quoted above imply. If this is correct, then there would be no obligation of Shemirah today, since there is no Mikdash which can become defiled by Teme'im. -M. KORNFELD.)
2. HA'GAON RAV CHAIM ZIMMERMAN zt'l (in "Agra l'Yesharim," ch. 1) suggests another practical difference between the reasons for the obligation of Shemirah. The Mefaresh (25b, DH Hayu) and the RA'AVAD (printed on 29a, DH Elu) explain that Shemirah was performed both during the day and at night. The RAMBAM (Hilchos Beis ha'Bechirah 8:2), however, writes, "Shemirah was performed the entire night," implying that it was performed only at night and not during the day. This appears to be the opinion of most of the Rishonim (see SEFER HA'CHINUCH #388, SEMAG, RASH, and BARTENURA at the beginning of Midos).
Rav Zimmerman zt'l explains that this dispute may depend on the reason for the Shemirah. If the reason for the Shemirah is to show respect to the Beis ha'Mikdash, then perhaps it was not necessary during the day, because the Avodah was performed during the day and many people were present then, thereby giving due respect to the Beis ha'Mikdash. If the reason for Shemirah, however, is to keep people who are Tamei out of the Beis ha'Mikdash, then there should be no difference between the day and the night.
2) DRYING AFTER IMMERSING IN A MIKVAH
OPINIONS: The Mishnah (end of 25b) teaches that when one of the Kohanim guarding the Beis ha'Mikdash becomes a Ba'al Keri, he must leave the Beis ha'Mikdash and go to the "Beis ha'Tevilah," where he immerses in the Mikvah. After he emerges, he dries himself -- "Nistapeg."
Does the Mishnah mention the fact that he dries himself after immersion because there is a Halachic obligation to do so, or does it mention that he dries himself merely because this is the normal procedure that is done after immersing, but there is no obligation to do so?
(a) The MISHNEH L'MELECH (Hilchos Avodas Yom ha'Kipurim 2:2) writes that the Gemara often mentions drying oneself when it discusses an obligation to immerse in a Mikvah. Also, whenever the Gemara mentions that the Kohen Gadol immerses himself, it mentions afterwards that he dries himself (see, for example, Yoma 31b). This implies that it is not merely a practical step in the immersion, but rather it is a Halachic requirement to dry oneself after immersion. This is also implied by the words of the RAMBAM (Hilchos Avodas Yom ha'Kipurim 2:2), who mentions that the Kohen Gadol dries himself after immersing on Yom Kippur.
The Mishneh l'Melech adds that the reason why the Kohen Gadol is obligated to dry himself is that if he would not dry himself, the water -- or hair or dirt that would stick to his body because of the water -- would be a prohibited Chatzitzah, an intervening substance, between his flesh and the Bigdei Kehunah (see Rambam, Hilchos Klei ha'Mikdash 10:6).
However, as the Mishneh l'Melech points out, according to this reasoning, the act of drying after immersion mentioned in the Mishnah here is not obligatory, because there is no law of Chatzitzah for a Kohen who is merely guarding the Beis ha'Mikdash. The Mishneh l'Melech cites support for this assertion from the fact that the Rambam (Hilchos Beis ha'Bechirah 8:7), in his summary of the Mishnah here, writes that after the Kohen immerses he returns to sit next to his fellow Kohanim. The Rambam mentions nothing about drying himself after immersion, implying that there is no Halachic obligation for him to dry himself in this case. The Mishneh l'Melech therefore concludes that the Mishnah here mentions that the Kohen dries himself after immersion merely because drying is the normal thing to do, but not because there is any obligation to dry himself in this case.
(b) RAV MOSHE FEINSTEIN zt'l in IGROS MOSHE (YD 2:86, DH veha'Nistapeg) writes that although it is not mandatory for the Kohen to dry himself after the immersion, the Mishnah does not mention drying merely because it is a practical part of immersing. Rather, the Mishnah is teaching an important Halachah -- that when the Kohen did not bring his own towel from home, he is permitted to use towels that are in the Beis ha'Mikdash which were purchased from money of the Sheyarei ha'Lishkah, even though being dry is not part of the Avodah. He is permitted to derive benefit from the towel, and he is not considered to be transgressing the prohibition of Me'ilah, is because of the principle of "Lev Beis Din Masneh Aleihen"; when Beis Din collects the public donations, Beis Din makes an unspoken condition that the money received from the public will lose its Kedushah if it is needed to purchase items such as towels for the use of the Kohanim.
Rav Moshe writes that according to this reasoning, why does the Rambam in Hilchos Beis ha'Bechirah not mention that the Kohen may dry himself with the towels of the Beis ha'Mikdash? He suggests that the Rambam is relying on his ruling elsewhere where he teaches that objects of Hekdesh are permitted because of "Lev Beis Din Masneh Aleihen." (For example, the Gemara in Kidushin (54a) states that the walls and towers of Yerushalayim were built from money of the Sheyarei ha'Lishkah, even though people clearly derived benefit from them for non-Hekdesh purposes; see Insights to Shekalim 10:2.) (D. BLOOM)

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

3) THE GUARDPOSTS OF THE KOHANIM AND THE GUARDPOSTS OF THE LEVIYIM
QUESTION: The Gemara explains that in the Sha'ar ha'Nitzotz, the Kohanim performed the Shemirah on the upper level, and the Leviyim performed the Shemirah on the lower level. The Mishnah in Midos (1:6) adds that in the Beis ha'Moked (which had no upper level), the Kohanim stood guard on the inside while the Leviyim stood guard on the outside.
The Gemara implies that the Kohanim and Leviyim stood guard at the same section of the Beis ha'Mikdash, but merely at different areas of those sections. How is this to be reconciled with the Gemara earlier (26a) which says that the Kohanim and Leviyim performed Shemirah in entirely different locations?
ANSWERS:
(a) The RAMBAM (Hilchos Beis ha'Bechirah 8:8) rules that the Leviyim performed Shemirah on five of the seven gates of the Azarah, because the Kohanim were already guarding the other two (Sha'ar ha'Moked and Sha'ar ha'Nitzotz). That is, at those two gates there were only Kohanim standing guard. How does the Rambam understand the Gemara when it says that the "Kohanim were on top and the Leviyim on bottom" at the Sha'ar ha'Nitzotz?
Perhaps the Rambam understands this statement as the MEFARESH does. The Mefaresh (DH sheha'Kohanim) explains that wherever the Kohanim guarded, they stood at a point of elevation ("on top"), while the Leviyim did not stand elevated. The Gemara means that the Kohanim guarded "on top" in their respective locations, while the Leviyim guarded "on bottom," on ground level, in their own locations.
(b) The ROSH quotes RABEINU TAM who says that the Leviyim guarded in 24 places. In three of these places they were together as subordinates to the Kohanim, while in 21 places they guarded by themselves. The SEMAG explains this way as well. According to this approach, the Mishnah is discussing only 21 guardposts of the Leviyim, since the Leviyim were not actually guarding in the three places where the Kohanim stood. Rather, the Leviyim were there merely to provide company and respect for the Kohanim who were guarding there ("v'Yilavu...").
(c) The ROSH himself and the PISKEI TOSFOS (#7) explain that the Leviyim guarded in only 18 places by themselves. They guarded together with the Kohanim in the other three places.
How do they understand the Gemara that implies that each Mishmar had its own individual place to guard? Perhaps they understand that since the Kohanim were above and the Leviyim were below, it was considered as though they were guarding at separate locations.

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