Halakhah su Levitico 23:3

The classic responsum that addresses the question of the impact of the changing time zones on halachic matters was authored by the Radbaz (Teshuvot Haradbaz 1:76) in the sixteenth century. The Radbaz writes that the end of Shabbat is determined by the advent of tzeit hakochavim (the appearance of three medium-sized stars) in the specific place that a person finds himself on Shabbat even if Shabbat has not yet ended in the individual's usual place of residence.¹¹⁰See Seforno to Vayikra 23:3, who adopts a similar approach.

There are those of our generation who calculate the Hebrew calendar. Because they know the calculation based on 1:12:793,⁸ A mean lunar month is 29 days, 12 hours and 793 halaqim. If we discard the four complete weeks from this figure, we have the “character” of 1 day, 12 hours, and 793 halaqim (1d, 12h, 793p). This is the amount of time that the molad proceeds through the week from month to month. Thus the molad advances monthly by 1d, 12h, 793p of a week. they think that they have discovered the principle of the calendar. They then examine the duration between the molad and the beginning of the night, and they tell the uncircumcised (Christians) when the moon will be visible.⁹ I do not know why the Christians, who use a solar calendar, need to know when the moon will be visible. Perhaps there is an error here in our texts and it should read “Arabs.” When they see that in their place the duration [between molad and sighting] is sometimes less that six hours,¹⁰ It sometimes happens that the molad is less than six hours before sunset yet the moon is visible that evening. they think that the time given for the molad applies to the location of each individual calculator. However, there are times when the moon is seen at the beginning of the night and sometimes there are seven or eight hours between the molad and dusk, and the moon is still not visible. Therefore, they think that the calculation of our calendar is incorrect. Heaven forbid! Rather they err, for they think they are wise. For a scholar cannot know when the moon will be visible until he does as I shall explain: He must know the moment of the molad. He should not assign to the night twelve hours. Rather he should begin to count from the beginning of the night until the moment of conjunction so many and so many hours.¹¹ He should count night followed by day on a 24-hour clock and not begin a new count with dawn. He should know where conjunction will take place as to the minute of the degree of the zodiacal sign. He should see if the sun’s path is long or short, and how long the path of the moon is. He should then add or subtract until he knows the moment of true conjunction for Jerusalem. He should then calculate how far this conjunction is from the beginning of the night by hours and minutes. If he is west of Jerusalem he should add to those hours the hours of his distance in longitude, or subtract hours if he is east of Jerusalem. He should know the daily distance that the sun travels in hours and add it to the place of the sun at the moment of true conjunction. He should do similarly for the position of the new moon based on its orbit. Then he should record in a chart the degrees of the zodiacal signs in his land, and take those degrees that he will find relative to the position of the sun. He should similarly do this in degrees relative to the moon, and subtract the smaller from the larger. Then he will find the arc of the chord (between the sun and the moon). He should find the positions of the nodes,¹² The nodes are the two points at which the moon crosses the ecliptic. They are called the “head” and the “tail” of the “dragon.” Berry (p. 48) explains: “The moon’s path on the celestial sphere is slightly inclined to the ecliptic, and may be regarded as a great circle cutting the ecliptic in two nodes, at an angle which Hipparchus was probably the first to fix definitely at about 5÷. Moreover, the moon’s path is always changing in such a way that, the inclination to the ecliptic remaining nearly constant, the nodes move slowly backwards from east to west along the ecliptic, performing a complete revolution in about 19 years.” so that he will know the latitude of the moon,¹³ There is a difference in the time of visibility of the moon if it is north of the ecliptic or if it is south of the ecliptic. in order to correct this arc. Then he should adjust the arc based on the correction of the sighting, both in longitude and in latitude. Then we will know the true arc of vision.¹⁴ This is the arc between the longitude of the sun and that of the moon. In order for the moon to be visible, an arc of vision of at least 12÷ is necessary. Then he will know when the moon will appear in each place for any desired month. One who knows these matters can understand the principle “If it is born before noon” (Rosh haShana 20b).¹⁵ The Talmud states: “If it [the moon] is born before noon, it will be seen before sunset; if it is not born after noon, it will not be seen before sunset.” In Sefer ha‘ibbur (p. 10b) Ibn Ezra explains this statement.

It is not convenient that the month begin with the time of mean conjunction nor of true conjunction, since not everyone can know these times. Therefore, the month begins when the moon’s light is newly visible to the eye. Such is written in the Mishna.¹⁸ See for example Rosh haShana 1:7. Here Ibn Ezra rejects Rabbi Saadia Gaon’s opinion that the Hebrew calendar is primarily a fixed calendar based on computation, and the need to observe the moon in order to declare a new month was only a temporary measure. (See Savasorda, Sefer ha‘ibbur, pp. 59–62.) Maimonides (Commentary to the Mishna, Rosh haShana 2:7) is very critical of Rabbi Saadia on this point and asserts that the primary method for setting the month and the holidays is by observation of the new moon. So just as the first month (Nisan), which is the month when the barley ripens, is recognizable by both an intelligent person and a fool, so the beginning of the month is recognizable by every person.

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.

The reason why such a thesis does not merit consideration is not immediately evident, particularly if there is no intrinsic reason why a day must be approximately twenty-four hours in duration.²⁷The Gemara, Shabbat 118b, speaks of commencing observance of Shabbat at an early hour in Tiberias and concluding its observance at a later hour in Sepphoris, i.e., observing Shabbat for longer than a twenty-four hour period. The principle that both the beginning and end of Shabbat is determined by local criteria would yield the result that a person traveling from Sepphoris to Tiberias would observe Shabbat for less than twenty-four hours.
R. Chaim Avraham Gatinyo, Tirat Kesef (Salonica, 5496), p. 5b, endeavors to demonstrate that Shabbat must be observed for a minimum period of twenty-four hours on the basis of the narrative recorded by the Palestinian Talmud, Kelayim 9:3 and Ketubot 12:3. R. Judah the Prince died on a Friday. The sun did not set that evening until much later than its usual time and hence observance of the Shabbat did not begin until that late hour. That miraculous phenomenon occurred in order that every participant in the funeral, including those who had traveled from other cities, might have sufficient time to return home and “prepare a barrel of water and kindle the lamp” before the advent of the Sabbath. Shortly after the sun finally set, the crowing of the rooster was heard. Experiencing daybreak so quickly after nightfall, people realized that they would not be observing a full twenty-four hour period as Shabbat. The populace feared “lest they had desecrated the Sabbath” during the period of time that the sun’s movement was arrested. Thereupon, a heavenly voice proclaimed that all those who had participated in the funeral of R. Judah were assured a portion in the world to come. Excluded from that promise was one individual, a laundryman who had not participated in the funeral. Shitah Mekubbeẓet, Ketubot 103b, cites a certain Rabbenu Kalonymus who explains that the populace had actually transgressed Shabbat prohibitions because the Shabbat had indeed begun at its proper time but people inadvertently failed to commence observance of the Shabbat in a timely manner because the sun was still high in the sky. Nevertheless, they were forgiven because of their participation in R. Judah’s funeral. The laundryman also failed to begin his observance of the Sabbath at the proper time for the same reason but because he was remiss in not participating in the funeral he was not forgiven. The laundryman was forgiven only subsequently when, out of great anguish, he hurled himself from a roof and died.
Rav Pe‘alim, II, Sod Yesharim, no. 4, disputes Tirat Kesef’s understanding of this narrative. Rav Pe‘alim asserts that there is no evidence that the Shabbat that occurred on the morrow of R. Judah’s death was less than twenty-four hours in duration. At first, people were confused, contends Rav Pe‘alim, because of the premature crowing of the rooster. The rooster’s circadian clock, he asserts, was attuned to a twenty-four hour cycle. Moreover, contends Rav Pe‘alim, there is no indication that the populace acted in an inappropriate manner (indeed, the heavenly voice may be construed as having endorsed their behavior) but only that they were afraid lest they had acted incorrectly. [Rabbi Tucatzinsky, Bein ha-Shemashot, p. 55, suggests that the populace acted correctly because the sun had not set. However, people were confused because they feared that the sun had indeed set and the illumination they perceived emanated from a supernatural source. Cf., infra, note 34.] Furthermore, argues Rav Pe‘alim, the Sabbath is to be observed on the seventh day “in all your habitations” (Leviticus 23:3), i.e., the occurrence of Shabbat is determined both at the beginning and end of the day by the setting of the sun in the locale in which a person finds himself, regardless of the length of the intervening day. R. Ephraim Zalman Margolies, Teshuvot Bet Efrayim, Yoreh De‘ah, no. 76, similarly disagrees with Rabbenu Kalonymus in asserting that Shabbat is determined solely by the setting of the sun.
Rav Pe‘alim further remarks that, having properly ushered in the Sabbath at sunset, it would be ludicrous to observe Shabbat for a portion of the following day in order to achieve a complement of a full twenty-four hours. See also R. Elijah Isaac Shemesh, Yedei Eliyahu (Jerusalem, 5790), no. 44. Thus, Rav Pe‘alim declares that a person who is able to travel long distances on Shabbat by employing a Divine Name or in some other miraculous manner may cease his observance of Shabbat immediately at nightfall in his new locale even though he has observed Shabbat for much less than twenty-four hours. That is also the position of a host of other authorities including R. Yechiel Michal Tucatzinsky, Bein ha-Shemashot, p. 55; Teshuvot Minḥat Elazar, IV, no. 42; Teshuvot Bnei Ẓion, III, Kuntres Midat ha-Yom, secs. 23-24; R. Alter Saul Pfeffer, Teshuvot Avnei Zikaron, II, no. 87, sec. 2; and R. Ben-Zion Abba Sha’ul, Or leẒion, I, Oraḥ Ḥayyim, no. 14. Cf., however, infra, note 60, as well as notes 65-66 and accompanying text. The only reason that suggests itself to this writer is that, although the beginning and end of a day and intermediate divisions of the day certainly depend upon local sundown and sunrise, the identity of any given day is the same throughout the globe with the minor exception presented by the necessary adjustment for the dateline. The dateline phenomenon is not an exception to the basic principle because that phenomenon is the logical result of the movement of the sun as perceived in all places throughout the globe except for the polar areas. The notion that in one locale it may be Shabbat while in another it may be some time on Friday and in another locale it may be some time on Sunday is readily understood. But a thesis that will posit that Shabbat can occur in some geographic area on a day that is, for example, Wednesday elsewhere is incompatible with the very nature of a calendrical system.