1) ONE WHO PERFORMS "SERITAH" FOR THE SAKE OF IDOLATRY
QUESTION: The Gemara quotes a Beraisa which teaches that one who performs Seritah as an act of mourning for a Mes is punished with Malkus, whether he does it by hand or with a utensil. One who does Seritah as a way of serving an idol is liable only when he does it with a utensil but not when he does it by hand (according to the Gemara's conclusion).
Why should one be Chayav for doing an act of Seritah for an idol? The Gemara earlier states that one is punished for Seritah only when he makes himself bleed out of mourning for the dead! Seritah is not related to serving Avodah Zarah.
ANSWERS:
(a) The RIVAN (DH Al Avodas Kochavim) explains that some forms of Avodah Zarah are performed through the service of making Seritos on one's flesh. If one makes a Seritah for a certain Avodah Zarah in the way that such a Seritah is normally made, even if that Avodah Zarah is not normally served in such a way one is Chayav Misah because it is considered a form of serving Avodah Zarah.
What does the Rivan mean that one is Chayav Misah for serving Avodah Zarah through Seritah even if that is not the normal way of serving that Avodah Zarah? The Gemara in Sanhedrin (60b) clearly states that one is Chayav Misah only for four forms of worship (and Seritah is not one of them) when one does not serve the Avodah Zarah in the way that it is normally served!
TOSFOS (DH Al) explains that the Rivan refers to the Chiyuv Malkus for performing Setirah for an Avodah Zarah that is not normally served in this manner. This punishment of Malkus is for transgressing the verse of "v'Lo Sa'avdem" (Shemos 23:24), which prohibits any act of deference to an Avodah Zarah (see Chart #12 to Sanhedrin 63a, footnote 11). However, one is not Chayav Malkus for performing Seritah with one's hand (according to the Gemara's conclusion), because performing Seritah by hand is not considered an act of deference at all since there is no Avodah Zarah that is served in that manner.
The RITVA suggests that the Gemara here refers to an Avodah Zarah with which no one is familiar. Since Avodah Zarah is normally served through doing Seritah with a utensil, if a person serves an unknown Avodah Zarah in that manner -- through Seritah with a utensil -- he is Chayav Misah, because it is assumed that this is the manner in which this Avodah Zarah is normally served. However, if he performs Seritah by hand, he is exempt from punishment because it is assumed that this is not the way the Avodah Zarah is served.
(b) The RAMBAM (Hilchos Avodah Zarah 12:13) explains that the Lav of "Lo Sisgodedu" is not limited to one who cuts his flesh for a Mes. It also applies to a person who cuts his flesh for an Avodah Zarah. (The KESEF MISHNEH explains that this is not a form of worship, but rather a way of beseeching the Avodah Zarah to respond to one's requests.) According to this interpretation, it is clear why the Gemara discusses one who cuts his flesh for Avodah Zarah when it discusses the Mishnah.
The Acharonim question the words of the Rambam. The Rambam himself writes that, unlike Gedidah, Seritah applies only when it is done in mourning for a Mes. If Seritah applies only when done in mourning, then how can the Rambam assert that the verse of Gedidah refers to one who cuts his flesh for Avodah Zarah? The Gemara states that according to Rebbi Yosi the source that Seritah is forbidden only when it is done as an expression of mourning is the logic that "Seritah and Gedidah are the same"; since Gedidah applies when done in mourning, Seritah also applies when done in mourning. If the laws of Seritah are learned from Gedidah, then the prohibition of Seritah should apply when done for Avodah Zarah as well, just like Gedidah! The Rambam cannot be ruling like the Rabanan who argue with Rebbi Yosi, because the Rambam rules (in Hilchos Avodah Zarah 12:13) clearly like Rebbi Yosi, that Seritah and Gedidah are the same, and one is Chayav for both whether he does it by hand or with a utensil (see IMREI BINYAMIN).
Perhaps the Rambam understands that when the Gemara says that Seritah and Gedidah are the same, it intends only to compare the prohibition of Seritah with the prohibition of Gedidah done in mourning, since an act of making oneself bleed out of pain is described by the Torah both by the expression of Seritah and by the expression of Gedidah. However, Seritah cannot be compared to Gedidah that is done for Avodah Zarah, since the Torah never describes an act of making oneself bleed for Avodah Zarah as "Seritah."
2) HALACHAH: WRITING ON ONE'S SKIN
OPINIONS: The Mishnah teaches that if one writes a Kesoves Ka'aka on his skin, he is punished with Malkus. However, he is Chayav only when he both writes with ink upon his skin and perforates his skin so that it will absorb the ink.
Is there any prohibition against writing upon one's skin without perforating the skin to make a tattoo?
(a) The RIVAN writes that even according to Rebbi Shimon, who says that one is Chayav Malkus only when he writes the name of an Avodah Zarah on one's skin, one is prohibited from tattooing any type of writing on one's skin. What is the Rivan's source for this ruling?
The BACH (YD 180) writes that the Rivan infers this from the wording of the Mishnah. Rebbi Shimon says that "one is not Chayav unless he writes the name [of an Avodah Zarah]." This implies that if one writes something other than the name of an Avodah Zarah, one is not Chayav Malkus, but he nevertheless is prohibited from doing so.
(The Gemara makes a similar inference form the Mishnah in Nedarim (18a) with regard to other Halachos. See, however, TOSFOS there (DH d'Katani) who proves that such an inference cannot be made every time this wording appears in the Mishnah. See also RAV CHAIM KANIEVSKY in KUNTRUS PAS'SHEGEN HA'KESAV (#18), who comes to the same conclusion based on a number of Mishnayos.)
Why does the Rivan find it necessary to make this point about Rebbi Shimon's opinion? Perhaps the Rivan follows the ruling of Rebbi Shimon in practice, based on the fact that the Gemara discusses the source for Rebbi Shimon's opinion. This indeed is the ruling of the RIF and the ROSH. Support for this ruling may be found in Gitin (20b; see Tosfos there).
The RITVA here challenges this ruling based on the fact that the Gemara cites the teaching of Rav Malchiya, who rules that a person may not place ashes on a wound, an act similar to making a Kesoves Ka'aka. According to Rebbi Shimon, who maintains that the Torah prohibits a Kesoves Ka'aka only when one writes the name of an Avodah Zarah, why should placing ashes -- which do not spell the name of an Avodah Zarah -- on a wound be prohibited mid'Rabanan? In order to answer this question, the Rivan writes that the Amora'im knew that Rebbi Shimon agrees that there is a prohibition against making a Kesoves Ka'aka even without spelling the name of an Avodah Zarah (see PAS'SHEGEN HA'KESAV).
Further support for the opinion of the Rivan may be found in the Tosefta (3:9), which teaches that one is liable for Kesoves Ka'aka only when he does it for Avodah Zarah. The Tosefta continues and says that one who makes a tattoo on his servant so that he will not run away is exempt from punishment, implying that even when one does not write the name of an Avodah Zarah it is still prohibited.
In any case, the MINCHAS CHINUCH (253:1) suggests that if it is correct to infer from the words "one is not Chayav unless..." that a prohibition exists, without Malkus, when one performs the act in a manner different from the way the Mishnah describes, then one may learn from the Reisha which says that "one is not Chayav unless one writes and perforates" that doing only one or the other (the writing or the perforating) is also prohibited (but is not punishable with Malkus).
It is not clear from the Rivan whether this prohibition is mid'Oraisa or mid'Rabanan. It seems more logical to assume that it is d'Rabanan, and that is why there it is not punishable with Malkus.
TOSFOS and the TOSFOS HA'ROSH in Gitin (20b) discuss the Gemara which refers to a Get written on the hand of a slave in the form of Kesoves Ka'aka. They write that the Get may be written in a manner which does not transgress the Isur d'Oraisa, since the Isur is transgressed only when done in a specific manner, as the Mishnah here describes. (That is, the Get may be written by first perforating the skin and then placing the ink on it, or by scarring the skin without adding ink.) However, they add that even such a manner of writing is prohibited mid'Rabanan, since the Gemara says that one is prohibited even from putting ashes on a wound, since it gives the appearance of a Kesoves Ka'aka (after the wound heals, the remains of the ashes are still visible beneath the skin), if not for the fact that the scar of the wound remains to show that it was not a Kesoves Ka'aka.
It might follow that writing without perforating should also be prohibited mid'Rabanan for the same reason, if the coloration will remain permanently.
(b) The TO'AFOS RE'EM (to the SEFER YERE'IM 338:3) infers from the fact that the Sefer Yere'im mentions no such prohibition that one is permitted to write on his skin (without perforating), even l'Chatchilah. The RAMBAM also makes no mention (in Hilchos Avodah Zarah 12:11) of any such Isur d'Rabanan, implying that it is permitted. Although the Rambam writes that if a person wrote on his skin but did not drive the writing into the skin "he is exempt," this does not necessarily imply that he maintains that such an act is prohibited l'Chatchilah. Only with regard to the laws of Shabbos does the Rambam (and the Gemara) use the word "Patur" to refer to an Isur d'Rabanan (for which one is "Patur" from punishment), as the Rambam writes at the beginning of Hilchos Shabbos. (See Minchas Chinuch 253:1, citing the MISHNAS CHACHAMIM #57; see also Minchas Chinuch 440:11 and 467:3, Pas'shegen ha'Kesav, and YAD MALACHI #526, in the name of the MORDECHAI and others.)
Rav Chaim Kanievsky (ibid.) points out that this is also the opinion of the ME'IRI in Gitin (20b).
HALACHAH: The Minchas Chinuch (253:1) concludes that one should not be lenient, and should avoid writing on the skin without perforating the skin because of the Isur d'Rabanan which Tosfos in Gitin mentions. However, he points out that the Isur applies only when the writing is done with a permanent form of writing which cannot be removed (which is very uncommon).
However, RAV CHAIM KANIEVSKY shlit'a mentions in PAS'SHEGEN HA'KESAV (#18), his treatise on the laws of writing a Kesoves Ka'aka, that the NIMUKEI YOSEF here writes that a Kesoves Ka'aka is "recognizable for a long period of time," implying that it does not need to remain on the skin permanently (but only for a long period of time) in order to be forbidden. Consequently, writing without perforating the skin should be prohibited even if the writing does not remain on the skin permanently.
Nevertheless, Rav Chaim Kanievsky writes that even if there is an Isur d'Rabanan, it applies only to scratching the skin without placing ink on the skin, or even branding a mark on the skin with a hot iron. However, writing on the skin without scratching the ink into the skin in no way resembles Kesoves Ka'aka, even if the ink remains on the skin for an extended period of time. (This implies that using a chemically-treated ink that penetrates the skin and remains there permanently is similar to Kesoves Ka'aka and should be prohibited mid'Rabanan.)

21b----------------------------------------21b

3) THE ACTION INVOLVED WITH WEARING "KIL'AYIM"
QUESTION: The Mishnah states that when a person wearing a garment of Kil'ayim is warned by witnesses (with Hasra'ah) to remove it, and he removes the garment and dons it again, he is Chayav Malkus. Rav Ashi explains that the person is Chayav Malkus even if he does not actually remove the garment but merely leaves it on for the amount of time that it takes to remove it and replace it.
Why should he be Chayav Malkus in such a case? All of the Poskim rule, like the Rabanan who argue with Rebbi Yehudah, that one is not punished with Malkus for a "Lav she'Ein Bo Ma'aseh." Since the person wearing the Kil'ayim did no Ma'aseh, why is he punished with Malkus? (RAMAH cited by the RITVA)
ANSWER: TOSFOS in Shevuos (17a, DH O Ein Tzarich) explains that in certain cases a person can be punished with Malkus even though he performed no action when he transgressed the Lav. When a transgression must be preceded by an action and the results of that action cause the person to continue to transgress the Torah's prohibition, the person is liable for Malkus for continuing to transgress the prohibition, since his transgression was brought about through an action. In the case of the Gemara here, a person can wear Kil'ayim only by donning the garment, which is an action. Therefore, as long as the Kil'ayim remains upon his body, he can be punished with Malkus, since the Kil'ayim reached its present position through his original action.
Tosfos gives another example of such a case. A Nazir enters a cemetery by traveling there in a closed box, and then another person opens the box and exposes the Nazir to the Tum'ah of the cemetery. If the Nazir does not leave the cemetery immediately, he can be punished with Malkus, because he could not have entered the cemetery (or the box) without performing an action. The RITVA here offers a similar answer. (See also SHA'AGAS ARYEH #32 and SHA'AGAS ARYEH CHADASHOS #12, IMREI BINYAMIN, and Insights to Nazir 17:1:d.)

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