Is there one seder, or two? Is Passover seven days long, or is it eight?
In Exodus, chapter 12, the Torah says, as plain as day, that the ritual meal commemorating the exodus from Egypt—the origin of the seder—shall begin at twilight on the 14th of Nisan. It does not say anything about a meal on the evening of the 15th day, or any other. The text goes on to say:
You shall celebrate a sacred occasion on the first day, and a sacred occasion on the seventh day; no work at all shall be done on them; only what every person is to eat, that alone may be prepared for you. You shall observe the [Feast of] Unleavened Bread, for on this very day I brought your ranks out of the land of Egypt; you shall observe this day throughout the ages as an institution for all time. In the first month, from the fourteenth day of the month at evening, you shall eat unleavened bread until the twenty-first day of the month at evening. (Exodus 12:16-18, JPS Translation)
How did we end up with the idea that Passover is celebrated for eight days, when the Torah says seven? Where do we get seders on the first two nights, when the Torah only mentions a special meal on the first night?
The answer is that the rabbis instituted an additional day to all of the Torah-commanded festivals (except Yom Kippur) because of a problem in reckoning dates. In the early centuries of the common era, the new month was declared by the actual observation of the moon in Jerusalem. A month could not begin until the first sliver of the new moon was actually sighted and reported to the Sanhedrin (the chief rabbinic council).
This, of course, created a problem for any community that was more than a day's travel from Jerusalem. A lunar month is approximately 29.5 days long. If you know what day the last month started, there are only two possibilities for the first day of the next month. It's either the thirtieth day after the last new moon or it's the thirty-first. But, how could people far from Jerusalem know which one to start on without a message from the Sanhedrin?
For Jewish communities in far away Babylon and Alexandria, information about the correct date could take weeks. The rabbis tried different methods to spread the news more quickly. A system of bonfires on mountain tops was instituted to announce the new month, but this system was easily foiled by opponents of the rabbis and Israel's enemies who set false fire signals.
Eventually, the rabbis adopted a system in which communities outside the land of Israel were required to observe Torah-ordained festivals on two days—one day that would be correct if the previous month had been 29 days long, and one that would be correct if it had been 30 days long. All of the rituals associated with Rosh Hashanah, the first day of Sukkot, Sh'mini Atzeret, the first and last days of Passover, and Shavuot were repeated for a second day. This second day of the holiday for the diaspora, yom tov sheini shel galuyot, is the reason for two seders and for a total of eight days of Passover.
In the fourth century, the rabbis switched to a calendar based on mathematical calculation of the lunar cycle instead of direct observation. This is the Hebrew calendar we still use. However, by that time, the practice of adding a second day to the holidays had been established as a permanent practice. In fact, the celebration of Rosh Hashanah as a two-day holiday had become so ingrained that it was observed even in Jerusalem, the city that knew the date of the new moon better than any other.
That's the way the holidays stayed until the Reform Movement arose in the 19th century. The early Reformers declared that the reason for the extra day of the holidays had disappeared more than a thousand years earlier, so they restored the biblical pattern of the holidays with only one day for Rosh Hashanah and seven days of Passover. However, the extra day of the festivals continues to be practiced today outside of the land of Israel by Orthodox and Conservative Jews. Inside the land of Israel, everyone observes the same holiday calendar.
Just to make matters even more confusing, many Reform congregations in the diaspora, for a variety of reasons, now have re-adopted the practice of observing two days of Rosh Hashanah. Also, many Reform congregations (like the one I serve) offer a congregational seder on the second day of Passover to bring the community together on one of our most cherished holidays. We may say that, as Reform Jews, we do not observe the second day of Passover as a full holiday, but, for practical reasons, we do offer a second seder.
Is the diversity of calendars and holiday practices good for Judaism or is it bad? I find that to be a difficult question to answer. I certainly have seen Jews—some Reform and some Orthodox—who become indignant about those "other" Jews who don't observe the holidays the "right way." That kind of partisan and chauvinistic attitude separates one Jew from another is certainly not "good for the Jews."
On the other hand, diversity within the family of the Jewish people can also be seen as a good thing. It keeps us thinking about why we do what we do and it opens up our minds to new possibilities. Reform Judaism has become better in recent decades because it has faced the challenge represented by Orthodoxy and has responded by re-imagining rituals that were once discarded—like immersing in the mikveh and wearing a talit—and has injected new life and meaning into them. Orthodoxy, too, has become better by adopting worship practices that were innovated by Reform Judaism—like communal singing in worship services and greater roles for women.
Whether you observed Passover this year with one seder or two, it is likely that your seder was different than the one your grandparents observed fifty years ago. That difference, in all likelihood, can be traced back to an influence inspired by the diversity of Judaism in the twentieth and twenty-first centuries.
Let a thousand seders bloom.
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