Why We Could Have Ended Asara B’Teveth At 3:30 in the Afternoon

Sources: Tur and Shulhan Aruch Orah Hayim 249, and the commentaries thereon.

The three fasts of 17 Tammuz, Tzom Gedaliah, and 10 Teveth are in a category entirely different from those of Yom Kippur (the only Torah-mandated fast), 9 Av (Rabbinically ordained, but on a higher level than the other three), Taanith Esther (A post talmudic practice not ordained by Hazal), and the Monday-Thursday fasts described in Masecheth Taanith for times of distress. The general rule is that when the latter fasts are called, they last until sunset, but as per the above sources, there is room, especially on Fridays, for both individuals fasting for their own reasons and for communities observing 10 Teveth to break their fasts once they have officially accepted the Sabbath, which this past Friday could have been as early as about 3:30pm.

More importantly, it is certain that in the olden days, any time in history in the land of Israel after the Mishnaic period and until the modern era, Jewish communities would have not observed 10 Teveth until nightfall on Friday.

Why? Unlike the modern era, streets became dark at sundown. Thus, people would try to get home quickly. This is the reason for Hazal’s assumption that half an hour after sunset, no one is really walking around outside. People used to recite the evening prayers at or around sunset, even during the week, so that they could get home before dark. Early Sabbath was a matter of halachic course. It was only later in history, when due to the influence of the Vilna Gaon and the advent of electric lights did we start to make sure to hold maariv services well after sunset all year round.

This past Friday, those in and around Jerusalem, who were treated to a blacked out blizzard and left their synagogues at around 5:15pm, realized that their predecessors would never have done such a thing. When 10 Teveth was Friday in the 1500’s, the inhabitants of Safed would not have waited for 20 minutes after sundown to gather for maariv. They would have been trapped in the dark and the cold coming home. Maybe in the snow, too. Instead, they would have gathered well before sundown, and started heading home for qiddush while there was still natural light.

The Hafetz Hayim points out that it was the Maharil who was personally strict to end such a fast at nightfall, but even the Maharil acknowledged that the straight halacha allowed the community to end the fast whenever they accepted the Sabbath by reciting the evening prayers.

Update for 5781:

It is my sincere hope that the we no longer have to fast on the aforementioned days, but because this year 10 Teveth will once again be a Friday, it is worthwhile to review the relevant sources. I can do no better than to refer readers to the sources brought by the both the Beth Yosef and the Vilna Gaon to Orah Hayim 249 and 562, especially the Tosafoth to Avoda Zara 34a. We should notice that the very idea that a fast day ends at nightfall, and not at sunset as is explicit in the Talmud, is on the assumption that the halachic “sunset” is per Rabbeinu Tam’s definition, and therefore practically indiscernible, thus necessitating that we wait until his definition of nightfall. But, if we still define sunset as the actual sunset, then it clear that that is when the fast should end. Secondly, regardless of when a fast day should end on a week night, when the fast is on Friday, the onset of the Sabbath effectively ends the fast, even before sunset or nightfall.