12 Things You Might Not Know About Passover

For practicing Jews, Passover is a time to remember their deliverance from captivity in ancient Egypt. It's one of the most important holidays on the Jewish calendar, and in the days before the first night's seder, families make preparations such as cleaning the home of chametz and planning for a week of meaningful dietary restrictions. Here are 12 facts about Passover that you wouldn't have learned from a yearly viewing of The Ten Commandments.

1. Firstborn sons need to fast for Passover.

The festival of Passover (or Pesach) commemorates the story of the Jews' escape from Egypt. The passover in question is when the houses of the observant Israelites in captivity were "passed over" as Egypt's first-born children were killed (although confusingly, in the Torah, the date the 14th of Nisan is referred to as Passover while the week-long celebration is the Festival of Matzot. They've since been combined into one celebration called Passover).

In celebration of the firstborns being saved, it is traditional for them to fast on 14 Nisan. If there are no children, the oldest member of the household fasts. If the firstborn is a daughter? That depends on the tradition of the community.

2. Passover lasts either seven or eight days.

The Torah says to celebrate Passover for seven days (the time between the Exodus and the parting of the Red Sea), but many Jews outside of Israel celebrate for eight. Traditionally each month of the Jewish calendar was determined by an astronomical observation and could be either 29 or 30 days long. After a new month was determined, messengers spread the word. For Jews who lived too far away for messengers to bring timely news of a new month, it was safest to celebrate for an extra day, so no matter how long the previous month was, the holiday was celebrated.

Eventually, the calendar was standardized and the eight-day custom was no longer needed. Today, some Jewish denominations outside of Israel (like Reform Judaism) celebrate the mandated seven days, while many others prefer eight days. In Israel, it's generally seven.

3. Leavened grains are a no-go at Passover.

One of the most important parts of Passover preparations is cleaning the house of chametz, or leavened food. Even the tiniest bit has to go. Because the Jews left Egypt in such a hurry, it's said they didn't have time to leaven their bread. To commemorate that, five grains (traditionally wheat, barley, rye, spelt, and oats) are banished from the house. Jews can spend weeks ensuring that the house is perfectly clean—and there are even professional chametz cleaning services that say they'll boil toys, break down and reassemble kitchen chairs … and possibly still leave the house dirty. There's a saying in Jewish households: "Dust is not chametz." The goal is to get rid of chametz above all else.

4. Matzo, which is made from wheat, is one of the most important parts of a Passover meal.

While there are restrictions against leavened products, one of the most important parts of a Passover meal is matzo, which is made from wheat. The difference between matzo and regular bread is that the wheat in matzo cannot come into contact with any water until it's ready to be cooked. And once water and wheat are mixed, it has to be baked within 18 minutes (sources differ as to whether the timer stops when it enters or leaves the oven). After 18 minutes, fermentation begins and it is chametz.

But why 18 minutes? Supposedly it's because that's how long it takes to walk between the cities of Migdal Nunaiya and Tiberias in Israel. Over the years, scholars have argued about how long it would actually take to walk between the cities, with some proposing that copying errors reduced the distance from circa four miles to one and thus reduced the time from 72 minutes to 18. Nowadays, it's felt that even if there was a transcribing error, there's enough tradition to use 18 minutes.

5. Grains get complicated during Passover.

As Jews spread around the world, they often found themselves faced with foods that weren't explicitly mentioned for Passover. Sephardic Jews (generally) feel that only the five expressly mentioned grains are forbidden, while Ashkenazi Jews worry that the dishes made from certain other plants that look similar and are grown in similar conditions as the forbidden grains will risk contamination between the two. So if these ingredients (called kitniyot, or "legumes") were avoided, actual chametz could more easily be avoided (although kitniyot is nowhere near as regulated as chametz).

But recently, some authorities have argued that improved technology and storing methods have rendered the old methods obsolete. It's a current debate in some communities.

6. Some of the best matzo flour is made in Arizona.

One of the most difficult parts of making matzo is keeping the flour dry before it's ready to be converted into matzo; any water risks converting flour into chametz. So, according to The New York Times, one sect of Hasidic Jews has found the perfect farming conditions to produce their wheat—the arid fields of southwestern Arizona. The group of ultra-Orthodox Jews from Brooklyn, New York, work with a farm in Yuma, Arizona, to ensure that no unwanted moisture affects the crop, and the resulting kosher wheat is shipped back east to make up to 100,000 pounds of matzo.

7. Pets also get special food during Passover.

For Passover, houses must be free of chametz and there can be no benefit derived from it. This includes pet food. In keeping with this, there are Passover-friendly pet foods out there, and some Rabbinical authorities propose switching out your pet's diet for a few days—such as giving dogs straight meat or herbivores a variety of approved vegetables. If a pet must have a specific type of food—or you can't get Passover-friendly pet food—some observant Jews follow the rabbinical authorities who give the option to sell the pet to a gentile for a few days and then get it back after Passover has ended.

8. There are six symbolic Passover foods.

The focal point of the start of Passover is the Seder plate, and on it are six ceremonial items:

Beitzah: A cooked egg, representing sacrifice (it's also been suggested that while most foods soften when you cook them, eggs get harder, representing the resolve of the Jewish people)

Haroset: A sweet mix of fruits, nuts, and honey/wine that symbolizes the mortar used by Jews during their enslavement

Karpas: A green vegetable signifying new life

Maror and hazeret: Bitter herbs (often horseradish for maror and something like romaine for hazeret) to represent the bitterness of slavery

Zeroa: A shank bone (or a chicken neck) to remember the Paschal sacrifice.

9. Sometimes an orange is added to the Seder plate.

In the 1980s, Dartmouth professor Susannah Heschel spoke on a panel at Oberlin College. While there, she met some students who told a story of a rabbi who said "There's as much room for a lesbian in Judaism as there is for a crust of bread on the seder plate." In response, they started placing a crust on their plates.

Heschel was inspired, but felt that using bread sent the wrong message, writing "it renders everything chametz … [suggesting] that being a lesbian is being transgressive, violating Judaism." So she proposed putting an orange (originally a tangerine) on the Seder plate to symbolize Jewish LGTBQ people. At some point, a story emerged that it was actually to symbolize women in general, but Heschel explained: "A woman's words are attributed to a man, and the affirmation of lesbians and gay men is erased. Isn't that precisely what's happened over the centuries to women's ideas?"

Other more modern additions include pine cones (symbolizing mass incarceration), an artichoke (to recognize interfaith families), or tomatoes or Fair Trade chocolate (to remember that there's still slavery around the world).

10. Some major companies produce special kosher-for-Passover food and beverages.

Many companies produce special kosher-for-Passover products, from chocolate syrup to cake mixes. But one of the most important is Coca-Cola. In the early 20th century, Rabbi Tobias Geffen was serving as an Orthodox rabbi in Atlanta. Due to his location (Coca-Cola was invented and is headquartered in Atlanta), he was frequently asked if Coca-Cola was kosher. After analyzing the product, he found two problem ingredients—alcohol and glycerin.

The alcohol was a problem because it was grain-derived and thus unacceptable for Passover, a problem that was solved by switching to fermented molasses. The other problem, however, was glycerin. The glycerin was derived from animals, and there was simply no economic way to ensure the animals were kosher. As Roger Horowitz explains in Kosher USA, there's an exemption in the rules for a tiny amount of an unacceptable ingredient—designed to cover mistakes—and Coca-Cola's glycerin content was dramatically below that level. Rabbi Geffen, however, believed that since the glycerin was deliberately added, it didn't qualify for this rule. Soon, though, a new source of glycerin from cottonseed oil emerged, and Coca-Cola was approved for Passover.

When Coca-Cola switched to high-fructose corn syrup, however, that created a problem for Ashkenazi Jews. As such, today there's a special yellow-capped Coca-Cola that doesn't use HFCS and is certified kosher.

11. Maxwell House coffee holds a special place at Passover.

But the most influential company is likely Maxwell House. In the 1920s they decided to expand their presence to Jewish families—but there was a problem. Colloquially known as coffee "beans," there was a view that they were legumes, and as such forbidden to Ashkenazi Jews. Soon Maxwell House convinced reluctant coffee drinkers that their product was acceptable, and in 1932 the company began publishing the Maxwell House Haggadah (the Haggadah is the telling of the Exodus and how to perform a seder meal). In the years since, Maxwell House estimates that it has published 50 million Haggadahs, which were even the preferred text for the Obama White House Seder.

12. The world's largest Seder happens in a surprising location.

Going on for more than 30 years and hosting over 1000 people, the Kathmandu Seder was started in 1989 by the Israeli ambassador to Nepal, who quickly realized that the demand was much higher than he was ready for. The ambassador contacted a rabbi friend who dispatched two rabbinical students to aid the preparations. The seder was a massive success—expecting 90 guests and hoping for 150, they ultimately had 500 guests.

Nowadays, preparations for the seder start months in advance, with 1000 bottles of wine and over 1000 pounds of matzo getting shipped in from the United States and Israel.

This article was originally published in 2018; it has been updated for 2022.