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Time Wars

The ancient rabbis were well aware that control of the calendar was linked to their authority over the Jewish people

The website IsitaJewishholidaytoday.com is an invaluable resource, but its usual accuracy recently hit a bump, as we have just passed the most contested period of the Jewish year. 

Though the start of the holiday of Shavuot was celebrated widely this past Tuesday night, the exact date of the festival has been a bone of contention for millennia. The ambiguity stems from the instructions given in Leviticus 23, which states that a certain type of offering (known as the Omer) should be initiated “on the day after the Sabbath,” and seven weeks counted from that point before celebrating Shavuot. The context makes clear that the Sabbath in question falls during Passover. But while the rabbinic tradition understands “Sabbath” as a general term for “holiday” (in this case referring to the first day of Passover), others have insisted that “the Sabbath” must refer to Shabbat. According to this view, the Omer ought to be offered, and the count begun, on the Sunday following Passover.

One result of this approach is that Shavuot would always fall on a Sunday, as is the case with the parallel Christian holiday of Pentecost (literally “Fiftieth”), which is celebrated 50 days after Easter. Sunday, the day on which Jesus was said to be resurrected, has always been important to Christians, who considered it the “Lord’s Day” even before it was designated as the Christian day of rest in 316 CE.

It is possible that the idea of Shavuot always falling on the holy day of a rival religion contributed to the rabbis’ insistence that the Shabbat in Leviticus 23 could not literally mean Saturday. Or perhaps the dispute had nothing to do with early Christianity and was simply a disagreement between rival Jewish sects. In a scene bordering on pantomime, the Mishnah (Menachot 10:3) explains how the Omer offering was harvested with enthusiastic audience participation and explicit disavowal of the ways of the Boethusians, a group that rejected the thinking the Mishnah considers authoritative. Interestingly, the Mishnah claims this harvesting would even happen on Shabbat, which is curious because this would mean that Passover began on Thursday night, which the rabbinic tradition is careful to make sure never happens.

Although Boethusians these days are few and far between, other contemporary groups refute rabbinic orthodoxy. Communities of Samaritans and of Karaites, who follow the literal instructions of the Torah and reject the interpretative tradition of the rabbis, do indeed count their Omer from the first Shabbat during Passover and will celebrate Shavuot this Sunday.

All this might seem a bit silly and irrelevant, but consider for a moment how much control of the calendar impacts society. This goes beyond which days we are granted paid time off from work, extending into more fundamental areas like how we understand time, authority and arguably even reality itself. That we have a seven-day week is possibly one of the Bible’s biggest impacts on the modern world, and is far from normative through human history. The Romans had a 10-day week, while the Mayan calendar’s shortest cycles are of 13 and 20 days.

When we declare that today is Shabbat and not simply Saturday, our subjective identity creates a frame through which we perceive objective reality. The same goes for considering this year 5784, rather than 1445, as Muslims do. That the global consensus says we are in 2024 implicitly recognizes Christian hegemony, and labeling the count CE (Common Era) rather than AD (Year of Our Lord) is a more or less superficial adjustment. This is why the power to decide time — and even, on occasion, to declare a radical new beginning — has long been a hallmark of revolutions. Correspondingly, the introduction of the Gregorian calendar in 1582 both broadcast the power of Rome to adjudicate time, and demonstrated the limits of its authority, with Protestant and Orthodox countries holding out against the change for almost 300 years. 

The rabbis were well aware that control of the calendar was intimately linked to their authority over the Jewish people. While the announcement of the official new moon was initially broadcast using mountaintop bonfires, it was replaced with human messengers to stop rival sects from corrupting the system. In a powerful and disturbing story, the Talmud also relates how Rabban Gamliel insisted that his own teacher Rabbi Yehoshua submit to his ruling on the correct timing of Rosh Hashanah, forcing Yehoshua to publicly profane the day he calculated to be Yom Kippur.

In our day, the traditional rabbinic power over time has diminished. Reform Jews dispense with the practice of celebrating two days of festivals in the diaspora, a hangover from the ancient messenger system. Many people take this autonomy further, for instance choosing the closest convenient weekend on which to hold a Passover seder.

And as for the correct day to observe Shavuot? According to the Talmud (Chagigah 17a), Shavuot should really last seven days — and indeed, elements of the ancient festival did, allowing pilgrims to complete all their offerings. Even though we do not keep a seven-day Shavuot, the fact that mourning practices are suspended for this week hint at its festive nature. And what’s more, according to the Torah itself, Moses was on Mount Sinai for 40 days and 40 nights, suggesting that Shavuot is really a multi-week period of revelation.

Perhaps appropriately for a festival celebrating the disruptive meeting of heaven and earth, the indeterminate timing of this holiday taps us directly into these deeper issues of calendar, authority and meaning.

So whichever way you cut it, is it a Jewish holiday today? Well, maybe.

This article initially appeared in My Jewish Learning’s Shabbat newsletter Recharge on June 15, 2024. To sign up to receive Recharge each week in your inbox, click here. 

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