Halakhah zu Schemot 31:13

Even Sabbath regulations, despite their status as testimony to the doctrine of divine creation, are suspended when life is in danger. The Gemara, Yoma 84b, declares, " 'For it is holy unto you' (Exod. 31:13)—the Sabbath is given over into your hands, but you are not given over into its hands." One talmudic explanation of the subordination of other laws to the preservation of life is based on the line of reasoning that it is preferable to violate one Sabbath in order that the patient be enabled to observe many Sabbaths (Yoma 85b). Implicit in this formulation is the notion that the observance of divine law must be maximized. In effect, a calculus of observance is established. Hence, temporary abrogation may be sanctioned for the sake of subsequent observance.

Here are honest witnesses that the day begins with dusk. Similarly for all the holidays and the Sabbath, for all are “appointed seasons of God, holy gatherings” (ibid. 23:4). Only the Sabbath is called “a Sabbath for God” (Exodus 20:10, Deuteronomy 5:14), for God rested during Creation. Since both the year and the day are dependent on the sun, for both motions are similar one to another, therefore the seventh year is comparable to the Sabbath day. Hence it is also written with regard to the seventh year “a Sabbath for God” (Leviticus 25:2). Therefore, just as the Sabbatical year begins with the autumn season, so the beginning of the Sabbath day is in that period of the day corresponding to autumn, which begins with dusk.

Said R. Yosi the son of Hanina: A gentile who observes the Sabbath prior to accepting circumcision upon himself is liable to the death penalty. Why? Because he was not commanded concerning it. And what causes you to say that a gentile who observes the Sabbath is liable to the death penalty? Said R. Hiyya the son of Abba in the name of R. Yoḥanan: In the practice of the world [if] a king and a courtesan sit and converse with one another, one who comes and interposes himself between them, is he not liable to the death penalty? So is the Sabbath between Israel and the Holy One, blessed be He, as it is said "between Me and between the children of Israel (Exodus 31:13)." Therefore, a gentile who comes and interposes himself between them prior to accepting circumcision upon himself is liable to the death penalty. The Sages said: Moses said before the Holy One, blessed be He, "Sovereign of the universe! Since gentiles have not been commanded with regard to the Sabbath, if they observe it, will you be gracious unto them?" Said the Holy One, blessed be He, "Of this you are afraid? By your life! Even if they observe all of the commandments of the Torah I will cast them before you."

It seems to this writer that Mor u-Kezi'ah regarded the establishment of halakhic time, and hence of the Sabbath, in the places under discussion to be a matter of unresolvable doubt. To be sure, as clearly enunciated by R. David ibn Zimra, Teshuvot ha-Radvaz, I, no. 76,⁸See also Parashat Derakhim, Drush 23, s.v. od nakdim; R. Israel Lipschutz, Tiferet Yisra’el, Berakhot, note appended to Bo‘az, end of chapter 1; R. Chaim Joseph David Azulai, Birkei Yosef, Oraḥ Ḥayyim 242:1; R. Joseph Saul Nathanson, Teshuvot Sho’el u-Meshiv, Mahadura Revi’a’ah, no. 154; and R. Benjamin Aryeh Weiss, Teshuvot Even Yekarah (Lemberg, 5654), no. 11. determination of the onset and conclusion of Shabbat is determined locally. Leviticus 23:3 mandates that the Sabbath be observed "in all your habitations." That phrase is understood by Radvaz⁹A similar interpretation of that verse was earlier advanced by Seforno in his commentary ad locum. See also the interpretation of Exodus 31:16 advanced by the Zohar, Genesis 56a. The verse “And the children of Israel observed the Sabbath to make the Sabbath for their generations (le-dorotam)” is rendered by the Zohar as “to make the Sabbath for their dwellings (le-dirotam).” as signifying that the onset and conclusion of Shabbat is to be determined in accordance with sunset at each particular "habitation."¹⁰R. Abraham ibn Ezra, in his commentary to Genesis 33:10, understands the verse “And the sun rose upon him” (Genesis 32:32) as reflecting this underlying solar phenomenon, i.e., the sun rose for Jacob in the locale in which he found himself but did not rise simultaneously in other areas.
R. Isaac di Trani, renowned as the author of Teshuvot Maharit, declares in his Ẓofnat Pa‘aneaḥ (Venice, 5413), Drush le-Parashat Bereshit, that the work of creation did not cease throughout the globe at a single instant. Rather, the process of creation came to a halt at each point when night fell at that spot. In effect, in observing Shabbat as determined by local sunset, man emulates the Creator who ceased from the process of creation at different times in different places. Ḥatam Sofer, cited by R. Israel David Jaffe, Ḥazon le-Mo‘ed, no. 8, sec. 7, also stated that this was the case during each of the six days of creation: the work of each day did not take place simultaneously throughout the world; rather, the entities created on each day of the week were created in every geographic area while it was day in that locale. This, Ḥatam Sofer asserts, applied even to the “ten things” which the Mishnah, Avot 5:6, declared to have been created on the sixth day between sunset and nightfall, i.e., those objects were created in different places at different times. Ḥatam Sofer interprets the verse “And God finished on the seventh day… and He rested on the seventh day” (Genesis 2:2) as referring, not to a single act of cessation of labor, but to a divine comportment at two different places, viz., God completed the work of creation at one locale while at the same time resting at another locale. See also R. Yechiel Michal Tucatzinsky, Bein ha-Shemashot (Jerusalem, 5729), p. 53; idem, Yomam (Jerusalem, 5703), p. 73; and R. Ben-Ẓion Uziel, Mishpetei Uzi’el, Oraḥ Ḥayyim, II, no. 29. Cf., R. Menachem Kasher, “Shabbat Bereshit u-Shabbat Sinai,” Talpiyot, vol. I, no. 1 (Tishri 5704), pp. 415-420.
Cf., however, Teshuvot Sho’el u-Meshiv, Mahadura Revi’a’ah, who candidly acknowledges that, in observing Shabbat according to local time “in all their habitations,” Jews do not observe Shabbat during the same time period in which the Creator ceased from the work of creation. Moreover, he regards that concept to be reflected in the otherwise problematic words of the musaf prayer: “a people who sanctify the seventh day (am mekaddeshei shevi‘i).” Jews sanctify the month and hence the festivals which are calendar dependent. Shabbat, however, is predetermined and does not require sanctification of the new moon by the Bet Din. Nevertheless, explains Sho’el u-Meshiv, since Jews must observe Shabbat “in all their habitations” at different times they are indeed a “people who sanctify the seventh day.” Shabbat is designed as a "sign between Me and between you" (Exodus 31:13) and accordingly, is to be observed during the period representing the culmination of six days of labor in each person's locale. The Sabbath day, which includes a period of darkness and a period of daylight, is roughly twenty-four hours in length in all places other than in the extreme northern and southern regions. As a result, the Sabbath is observed on the same day of the week in all parts of the globe. Accordingly, Mor u-Kezi'ah assumes that in locales in which that cannot be the case there is no discernible method for determining the days of the week. Hence, determination of the advent of Shabbat remains either a matter of irresolvable doubt or, alternatively, there is no concept of halakhic time in such places. Therefore, Mor u-Kezi'ah rules that a person finding himself in such a place faces a problem that is no different from that confronting a person lost in the desert or confused with regard to a sequence of days and must conduct himself in an identical manner. That is precisely the import of Mor u-Kezi'ah's concluding phrase "in the manner indicated earlier with regard to one who travels in the desert," i.e., he may perform no forbidden act on any day of the week and must recite kiddush and havdalah on the seventh day of every seven-day cycle subsequent to his arrival.