Êxodo 31:16 Halacá: Gray Matter II & Kitzur Shulchan Arukh

The Tur (Orach Chaim 561) writes that one must rend his garments upon seeing “cities of Israel” in ruins. Rav Yosef Karo (Beit Yosef ad loc.) notes, however, that the Gemara mentions only cities in Judea, so the Tur’s reference to cities from anywhere in the Land of Israel is not specific.⁴¹. The Gemara derives this principle from the verse “And the Jewish people shall guard Shabbat” (Shemot 31:16). Rashi (s.v. Veshamru) explains that “guarding” any particular Shabbat includes ensuring that future Shabbatot will also be observed. (The same Hebrew word - “lishmor” - means both “to guard” and “to observe.”)

The Gemara (Yoma 82a) asserts that piku’ach nefesh overrides every Torah law except for the prohibitions of idolatry, sexual immorality, and murder. A few pages later (85a-85b), it offers numerous sources for why piku’ach nefesh overrides Shabbat. Rabbi Elazar ben Azariah reasons that if circumcision overrides Shabbat despite affecting only one organ of the body, so the vital needs of the entire human body surely override Shabbat.²The Gemara thoroughly discusses the laws of circumcision on Shabbat in the nineteenth chapter of Shabbat. Rabbi Shimon Ben Menasya presents the famous principle, "Violate one Shabbat for [the endangered individual’s] sake so that he will observe many future Shabbatot.”³The Gemara derives this principle from the verse “And the Jewish people shall guard Shabbat” (Shemot 31:16). Rashi (s.v. Veshamru) explains that “guarding” any particular Shabbat includes ensuring that future Shabbatot will also be observed. (The same Hebrew word - “lishmor” - means both “to guard” and “to observe.”)
Although this reason implies that we may save only a Jew’s life on Shabbat in order that he will observe future Shabbatot, the Biur Halachah (329 s.v. Ela) writes that in practice one should violate Shabbat even to save a Jew who clearly will not observe Shabbat in the future (see, also, Halichot Olam 4:226 and Teshuvot Minchat Shlomo 2:34:39 and 40). Shmuel adds that the Torah (Vayikra 18:5) urges us to “live” by its laws (“Vachai bahem”), implying that observing the Torah should not cause death (“Velo sheyamut bahem”).

If one is being forced to transgress even a serious sin for the moment,²⁶Even idolatry. Where there is a possibility that he may be willing to die rather than transgress, it is obligatory to violate Shabbos to save him. [Mishnah Berurah 328: 31] the Shabbos should not be violated in order to save him from committing the transgression. But, if he is being forced to convert and to leave the fold of the Jewish people, even if he is a minor, it is obligatory to exert all effort to save him, even if it is necessary to violate Shabbos by [transgressing] a d'oraisa prohibition,²⁷Concerning a minor, the author accepts the ruling of Eliyahu Rabba, as does the Mishnah Berurah. Chayei Adam (68: 13), however, allows violating only d’rabanan prohibitions. just as it is obligatory to violate Shabbos for someone who is critically ill; for it is written:²⁸Exodus 31: 16. "The people of Yisrael shall keep the Shabbos." The Torah tells us: Violate one Shabbos for his sake so that he may keep many Shabbosos. Even where it is doubtful whether the intervention will succeed or not, nevertheless it is obligatory to violate Shabbos and attempt to do whatever is possible, just as we violate [Shabbos] for a possible life-threatening situation. However, one who is faithless and wants to convert, Shabbos must not be violated for him [by doing] a d'oraisa prohibition, because since he is at fault, we do not say to anyone: "Sin for the benefit of your friend." Nevertheless, when it involves a d'rabanan prohibition, such as walking beyond the techum, or to ride a horse, or to ride on a wagon, as well as handling money; according to some poskim it is permissible to violate Shabbos to save him.²⁹Eliyahu Rabba, Peri Megadim, Mishnah Berurah 306: 56. Magein Avraham (254) disagrees.