Halakhic Night

The determination of “night” in halakhah is a topic that is highly complex and controversial. It is understood that the shift from day to night is a process, thus complicating the issue of pinpointing a moment of transition; further, much disagreement exists as to the identification of the markers of the process; and, as well, different areas of halakhah may use different definitions. (For example, kodashim may use a different standard; see Tosafot, Zevachim 56a, s.v. minayin, and Chiddushei Chatam Sofer, Sukkah 38a, s.v. mi.).

Much of the debate has centered around the resolution of two statements attributed by the Talmud to R. Yehudah. In Shabbat 34b, the period of bein ha-sh’mashot (in between sh’kia and tzet hakokhavim) is identified by R. Yehudah as three quarters of a mil. If a mil is understood to be 18 minutes (a questionable assertion, as will be discussed later), then it emerges that tzet hakokhavim is 13½ minutes after sh’kia.

However, a different impression comes from Pesachim 94a. There, in a discussion concerning the dimensions of the Earth, R. Yehudah states that in between sh’kia and tzet hakokhavim there are four mil. Again assuming an 18 minute mil, that would result in a bein ha-sh’mashot of 72 minutes; quite a difference from the first statement.

The resolution of this contradiction is at the root of a major dispute associated, on the one side, with the geonim and the Vilna Gaon (Gra), and on the other side, with Rabbeinu Tam. According to the first school of thought, of which the geonim (See Resp. Maharam Alashkar, 96, citing R. Sherira Gaon and R. Hai Gaon) and the Gra (see Biur to Sulchan Arukh, 261:2) represent different versions, the statement in Pesachim is not applicable to the halakhah in these cases. Thus, ¾ of a mil after shkia is tzet hakokhavim, and the time in between is bein hashmashot.

Rabbeinu Tam (see Tosafot, Berakhot 2b, s.v. dilma; Shabbat 35a, s.v. trei; Pesachim 94a, s.v. R. Yehudah), however, resolves the issue differently. In his assessment, there are actually two points called sh’kia The first sh’kia takes place when the sun begins to sink beneath the horizon The second sh’kia refers to the point once the sun has already sunk. The four mil period refers to the time in between the first sh’kia and tzet, while the ¾ mil period is the time from the second sh’kia until tzet. (A third opinion exists, as well; see Sefer Yereim, 274).

Powerful support exists for both sides. On the one hand, the position of the geonim is effectively expressed by the Gra’s statement that Rabbeinu Tam cannot be right because hachush makhchish, “one’s senses contradict it”: a glance outside the window will verify that it is pitch black long before four mil have passed from the time of sh’kia. Indeed, much of k’lal Yisrael h in modern times has accepted the position of the ge’onim.

However, Rabbeinu Tam’s position also comes with much support, as it is actually the view of many other rishonim as well, up to and including the Shulchan Arukh (Orach Chaim 261:2) and the Rama (see also Magen Avraham, 331:2, and Resp. Chatam Sofer, O.C. 80.). Thus, many are machmir to not end Shabbat until “Rabbeinu Tam z’man”, a practice advocated by R. Moshe Feinstein (Resp. Iggerot Moshe, Orach Chaim IV, 64) and considered normative by communities such as Satmar (see Resp. Divrei Yoel, 18). On the other hand, R. Herschel Schachter and R. Mordechai Willig (see Am Mordechai to Berachot, 2) consider the view of the geonim to be dominant.

That position, though, also has issues of “chush” to be explained, although they are not as stark as those confronting Rabbeinu Tam, and are to some extent already addressed by the Gra himself. If one assumes the period of bein hashmashot to be ¾ of a mil, and if that is understood to mean 13 ½ minutes, it does not seem to be the case that darkness has already descended once that much time has passed since shkia. The Gra thus notes that this measurement is not meant to apply to every part of the world, but only to Israel and Babylonia (which share the same latitude). However, R. Yechiel Michel Tukichinsky, in his Bein HaShmashot, notes that even in Jersualem, stars are not visibible until about 22 minutes after shkia. R. Yehudah Levi (Z’manei HaYom B’Halakhah) observes that there is a difference in this area between the trained eye and the untrained eye. In Jerusalem (during the month of Nissan) an expert can discern three stars after about 15 minutes, a time not significantly different from ¾ of a mil.

It is noteworthy that identifying the exact moment of “night” has two types of ramifications. One the one hand, it indicates when the date, or day of the week, has shifted to the following one. In addition, it also tells when it is “night” for the purposes of halakhah. Thus, when Bein HaShmashot is identified by the gemara (Shabbat 34b) as being a safek, the connotation would appear to be that there are two undetermined aspects: whether or not it is night, and whether or not the day has changed.

The Radbaz (Responsa, 1442) brings this understanding into a resolution of an apparent contradiction in the words of the Rambam. In Hilkhot Shabbat (5:4) he writes that due to the indeterminate nature of Bein HaShmashot, one may not work on Friday night after sh’kiah. However, in Hilkhot Kiddush HaChodesh (2:9) he rules that despite the fact that sanctifying the new month can only take place during the day, after sh’kiah is still acceptable within that definition. The Radbaz thus asserts that perhaps the two issues in defing night are independent of each other. Thus, Friday can [possibly] switch over to Shabbat, while still maintaining the character of “day”. (For other resolutions to this problem, see Chavatzelet HaSharon al HaTorah, Bereishit, p. 8).

R. Moshe Shternbuch (Moadim U’Zmanim, II, 155, fn. 1) considers the question of those parts of the world where darkness never actually sets in. He suggests that the day changes at whichever point the distance between those places and the sun is the greatest, but that halakhic “night” does not take effect at all. Thus, one living in those areas would be unable to fulfill any mitzvot dependant on night. He does consider, without a conclusion, that k’riat shma might be an exception, as the controlling terminology is not “day” and “night” but rather “lying down” and “rising”.