Many years ago, someone asked me (perhaps earnestly, perhaps sassily — it was hard to tell) if Jewish holidays are celebrated for two days, why Yom Kippur is only observed for one. I laughed dismissively. Are you kidding? One day of fasting is enough. Fasting for two days? Absolutely not!
Little did I know then about a lovely little sugya on today’s daf.
For context, the Gemara has been discussing the observance of two-day holidays outside of Israel. Before learning to calculate the moon’s phases precisely, Jews outside Israel relied on messengers to tell them when the new moon had been sighted and declared in Jerusalem. But the messengers took some time to arrive and things could get confusing, so major holidays were (and for many, continue to be) celebrated for two days in the Diaspora, ensuring their observance aligned for at least part of the time.
But this is not the case with Yom Kippur, and the reasons are pretty obvious: If a daylong fast is rough, fasting for nearly 50 hours is a terrible, life-endangering idea, as alluded to in the Jerusalem Talmud.
But on today’s daf, we learn that not everyone respected that bit of common sense:
The Gemara relates that Rava would regularly sit in observance of the fast of Yom Kippur for two days, in case Elul had been declared a thirty-day month and Yom Kippur should be observed on what was observed in Babylonia as the eleventh of Tishrei. It once happened in accordance with his opinion. Elul had been declared a thirty-day month, and he was the only one who observed Yom Kippur on the correct day.
So at least one of our ancestors would fast for two days of Yom Kippur. Yikes.
Now perhaps you’re thinking this idea died back in Rava’s time. Nope! The 13th-century work Sefer Mitzvot Katan acknowledges that some people fast for two days, “but it is an additional stringency.” Going a bit further, Peretz ben Elijah of Corbeil quotes Meir ben Baruch of Rothenburg as saying that anyone who fasts for two days on Yom Kippur must do so forever, since once this particular commandment has been accepted it cannot later be surrendered.
Centuries later, Rabbi Moshe Isserles, better known as the Rema and the author of a commentary on the Shulchan Arukh, ruled that this practice should not be followed because it’s dangerous. Nevertheless, it must have persisted in the next century and beyond, because several major authorities discussed the ritual and liturgical implications of a two-day fast.
As the Jerusalem Talmud suggests, the possibility of serious self-harm is reason enough not to fast for two consecutive days. And if my response to the inquiry mentioned in the opening paragraph wasn’t clear enough, the practice is virtually unheard of these days. While appreciating the piety of Rava and others, it’s easier, safer and healthier to find other ways of expressing our devotion.
Read all of Rosh Hashanah 21 on Sefaria.