Performing Melachah During Bein Hashemashos
Question: During bein hashemashos at the end of Yom Tov, is it permitted to perform those melachos which are permitted on Yom Tov?
Discussion: It is definitely prohibited to perform melachah during bein hashemashos (twilight) for the sake of the next day, since bein hashemashos might still be day, in which case one would be doing melachah on Yom Tov for the sake of after Yom Tov.180 The question arises, though, as to whether it is permitted to perform melachah during bein hashemashos for bein hashemashos itself. R’ Akiva Eiger (Nedarim 69b; glosses to 495:1) raises the following potential issue: As mentioned, within the time frame of bein hashemashos, it is unknown exactly at which point day gives way to night. Therefore, it is possible that when the melachah is being done it is still daytime (i.e., Yom Tov), but when the food will be eaten, or when benefit will be had from the melachah, it will already be nighttime (i.e., after Yom Tov). According to this, R’ Akiva Eiger notes, it should be prohibited to light a candle during bein hashemashos even for immediate use, since it is possible that the candle is being lit at the last moment of the day, and one is benefiting from its light only the next day. However, he notes that, since the Poskim make no mention of such a prohibition, it would seem to indicate that it is permitted.
To explain why this should be so, R’ Akiva Eiger argues that this could be considered a case of sfek sfeika (a double uncertainty): Perhaps no melachah is taking place because Yom Tov is over. Even if melachah is taking place, perhaps the person will benefit from it before Yom Tov is over. Prohibited melachah is taking place only if it is now Yom Tov and the benefit will be derived after Yom Tov. Yet he notes that, since this act will definitely be permitted after nightfall, it is considered a davar sheyesh lo matirin (something which will eventually be permitted without question); as such, even a sfek sfeika is prohibited. There are Poskim181 who explain why this might nevertheless be permitted and, indeed, one should not object to those who act leniently. However, in deference to the words of R’ Akiva Eiger, most Poskim rule that one should refrain from performing Biblical melachah during bein hashemashos at the end of a Yom Tov day, even if the benefit will be immediate.
180 Beiur Halachah 503:1, ד"ה ביום טוב.
181 See Minchas Shlomo, Tinyana, 45; Cheshev Ha’eiphod III:90; Teshuvos Vehanhagos II:325; Megillas Sefer, Inyanim, O.C. 27. Orchos Rabbeinu (5753 ed.) II, p. 125 writes that Chazon Ish ruled leniently.