Abrahamic / Middle Eastern Judaism Passover Observance in Israel and the Diaspora Why Is Passover 7 Days in Israel? Share Flipboard Email Print Passover seder plate. Stephen Simpson/The Image Bank/Getty Images Judaism Important Holidays Basics Culture Prayers and Worship By Ariela Pelaia Updated March 12, 2018 Passover (also called Pesach, פֶּסַח) is one of the most central holidays in Judaism, and it is celebrated each year in the spring beginning on the 15th day of the Hebrew month of Nissan. One of the shalosh regalim, or three pilgrimage festivals, the holiday commemorates the miracle of the Israelite Exodus from Egypt. The holiday features countless rituals and traditions, including the Passover seder, abstaining from leavened food and eating matzah, and more. But how many days does Passover last? It depends on whether you're in Israel or outside of the land, or what Israelis call chutz l'aretz (literally "outside the land"). Origins and the Calendar According to Exodus 12:14, the Israelites are commanded to observe Passover for seven days: "This is a day you are to commemorate; for the generations to come you shall celebrate it...for seven days you are to eat bread made without yeast." After the destruction of the Second Temple in 70 CE and the Jewish people became more greatly scattered around the world than they had been during the Babylonian Exile after the destruction of the First Temple in 586 BCE, an extra day was added to the observance of Passover. Why? The answer has to do with the way the ancient calendar worked. The Jewish calendar is based on the lunar cycle, not like the solar-based secular calendar. The ancient Israelites didn’t use nifty wall calendars to track the dates like we do today; rather, each month began when witnesses spotted the New Moon in the sky and could identify that it was a Rosh Chodesh (the head of the month). To identify a new month, at least two male witnesses of the new moon were required to testify about what they had seen to the Sanhedrin (supreme court) based in Jerusalem. Once the Sanhedrin verified that the men had seen the correct phase of the moon, they could determine whether the previous month had been 29 or 30 days. Then, news about the start of the month was sent from Jerusalem to places far and wide. There was no way to plan more than a month in advance, and because the Jewish holidays were set to specific days and months—unlike Shabbat, which always fell every seven days—it was impossible to know for sure when the holidays were from month to month. Because it could take some time for news to reach territories outside of the land of Israel—and because mistakes could possibly be made along the way—an extra day was added to the observance of Passover in order to prevent people from accidentally ending the holiday too early. Adopting a Calendar The next question you're probably asking yourself is why, with modern technology and the ability to easily set the calendar, Jews haven't simply adopted the standard seven-day observance outside the land of Israel. Although the fixed calendar was put into use in the 4th century CE, the answer to this frustrating question originates in the Talmud: "The sages sent [word] to the exiles, ‘Be careful to keep the customs of your forefathers, and keep two days of the festival, for someday the government may promulgate a decree, and you will come to err'" (Beitzah 4b). At the outset, this doesn't seem to say much about the calendar, except that it's important to observe the ways of the forefathers, lest one be led astray and errors are made. How to Observe Today Globally, outside of Israel, Orthodox communities continue to observe the eight-day holiday, with the first two days and the last two days being strict holidays when one must abstain from work and other activities as one would on Shabbat. But there are those within the Reform and Conservative movements who have adopted the Israel-style seven-day observance, where only the first and last day are observed strictly like Shabbat. Also, for Jews living in the Diaspora who happen to be spending Passover within the land of Israel, there are a whole host of opinions on just how many days these individuals should observe. The same goes for Israelis who are living temporarily in the Diaspora. According to the Mishna Brurah (496:13), if you live in New York but are going to be in Israel for Passover, then you should continue to observe the eight days you would if you were back in the U.S. The Chofetz Chaim, on the other hand, ruled along the lines of "when in Rome, do as the Romans do," and said that even if you're a citizen of a Diaspora country, you can do as Israelis do and only observe seven days. Likewise, plenty of rabbis say that if you're someone who visits Israel for all of the shalosh regalim consistently every year, then you can easily adopt the seven-day observance. When Israelis are traveling or living temporarily abroad, the rules are different even still. Many rule that such individuals can only observe the seven days (with the first and last days being the only strict days of observance), but that they must do so privately. As with all things in Judaism, and if you're traveling to Israel for Passover, talk to your local rabbi and make an informed decision about what you should observe.