As we approach Pesach, a general feeling of dread falls over many of us as we face the monumental task of removing all our chametz.

The prohibition against owning or consuming chametz on Pesach is clearly defined in Shmot, 12:15-19. The Rambam lists chametz as products derived from wheat, oats, spelt, barley and rye (Chametz u’Matzah 3:11).

Over the centuries, many poskim (halachic decisors) have included legumes in the category of prohibited items on Pesach. In this article, we’ll take a closer look at the history of the ban on kitniyot (non-chametz grains and legumes) and what common practice is today.

The Gemarah in Maasechet Pesachim 40b says that the custom was to prohibit the cooking of a dish called chasisi on Pesach, as it could be confused with chametz. Many rabbinic commentators explain that chasisi was a type of legume and thus established a talmudic basis for the prohibition against consuming kitniyot on Pesach.

During the middle ages, most Jewish communities had little contact with one another. Travelling to a different community was expensive, time consuming and fraught with danger. As a result, most communities established minhagim (customs) that were unique to that community.

When contact between communities improved and customs began to spread, rabbinic authorities had to deal with new practices and render halachic decisions for their own community. Previously unknown foods were introduced and had to be dealt with according to Halachah.

Communities in the Middle East and North Africa ate many types of legumes year round, and thus were accustomed to the differences between chametz grains and non-chametz grains.

Most Ashkenazi communities, however, weren’t accustomed to eating non-chametz grains such as rice because of their lack of availability, and rabbinic authorities prohibited their consumption on Pesach out of fear that confusion between grains would lead them to violate the severe prohibition against owning and consuming actual chametz.

This problem was compounded by new species of grain native to the Americas. Corn (maize), potatoes and other grains previously unknown to Jewish communities were examined to determine their permissibility. In many cases, poskim ruled on the side of caution, and ruled that these crops should be avoided for the duration of Pesach.

Over the next few centuries, several species of crops became staples of their respective communities. Potatoes, for example, are commonly eaten among Ashkenazim during Pesach. However, there were poskim, most notably Rabbi Avraham Danzig, known as the Chayei Adam (1748-1820), who decided that they too are kitniyot and should be avoided. Thankfully, this opinion never caught on.

Other recent grain-like foods have come under much debate with regard to their kitniyot status. Quinoa, a plant native to South America, is considered kitniyot by some Ashkenazi poskim, while others allow it.

In many cases, Sephardi communities, which traditionally did not adopt the ban on kitniyot, became more strict regarding its consumption on Pesach. Many Sephardim will not consume rice on Pesach, while those who do undertake the extremely laborious practice of checking each and every grain to ensure that no other grains have mixed in. This is necessary, as food production has changed considerably during the last century, and grains are commonly mixed with other species.

The prohibition with regard to kitniyot is not nearly as severe as that against actual chametz. One may own and benefit from kitniyot on Pesach, for example by feeding it to one’s pet. Many medications manufactured today use corn-based ingredients, and these too may used on Pesach by those who are ill. Actual chametz must be completely avoided, unless immediately necessary to save one’s life.

As in all cases, if you’re uncertain as to what to do in a given circumstance, ask your own rabbi for guidance.

Chag Kasher v’Samyach!