As we enjoy the holiday of Pesach, our rabbis tell us to study the laws of the holiday in depth so we know what is and isn’t permitted. In the past, I’ve attempted to cover several of the many laws that surround Pesach. This year, I thought it better to study the history and laws surrounding a prayer that will be said on the last day of Pesach. One that is accepted by most streams of Judaism, it’s said in congregations worldwide several times of the year, including the last day of Pesach. It’s the prayer simply known as Yizkor.

The Yizkor service is unique within our liturgy, as it attracts Jews of all stripes to shul, including those who wouldn’t normally attend a service the rest of the year. This has given rise to the somewhat derogatory term of “Yizkor Jews.” We all know who they are: those who come to shul halfway through the service, with their tallit and kippah slightly askew, looking for a seat in the back. As soon as the prayer is said, they vanish from the synagogue until the next holiday rolls around.

But what is this prayer of Yizkor all about? Why does it attract even the least affiliated to shul at least once a year?

Yizkor comes from the word “zachor” (remember). The Yizkor prayer was originally instituted by our rabbis during the Yom Kippur service when the Shulchan Aruch states it’s most appropriate to recall the merits of our deceased loved ones in order to elevate their souls to a higher realm within heaven. In their memory, we commit ourselves to perform good deeds, study Torah and give charity, thereby annulling evil decrees on the holiest day of the year.

Over time, many Ashkenazi communities adopted the Yizkor service on the final day of each of the Shalosh Regalim (Pesach, Shavuot and Sukkot) in order to temper the frivolity that accompanied the holiday, and to encourage synagogue attendance (and thereby increase donations). Most Sephardi synagogues don’t recite the Yizkor prayer, but rather entreat those in the congregation who have lost loved ones to come forward and recite Bakashot (requests for divine mercy).

During the Middle Ages, the Crusades led to brutal persecution of Jews, and many were massacred on blood libel charges around Pesach. Many Rishonim (early rabbinic authorities), such as Rashi and the Maharil, encouraged communities to adopt the custom of reading aloud the names of those martyred during Yizkor. It was during this period that the melancholic tune used by chazzanim today was first introduced.

Most Ashkenazi and chassidic synagogues today have adopted the Yizkor prayer in one form or another. The custom is for the congregation to recite K’El Maleh Rachamim for their deceased loved ones, while those who have not lost a close relative step outside so as to not incur an ayin hara (evil eye).

There is no halachic obligation, however, for one to leave the sanctuary during Yizkor. In fact, many shuls say two extra K’El Maleh Rachamim prayers at the beginning of the Yizkor service for the six million Holocaust victims and for Israel’s fallen soldiers, respectively. During these two sets, it’s most appropriate for everyone to stay and participate.

There are varying customs with regard to who recites Yizkor and for whom. The obligation is incumbent upon all men and women over the age of bar and bat mitzvah who have lost an immediate relative (parent, sibling or child). Contrary to widespread belief, one does say Yizkor for a deceased parent during the first year.

Whether you’re obligated to recite Yizkor this year or (hopefully) not, take the time this Pesach to remember the countless Jews who perished through the generations defending our religion and our nation. In this merit, may we see the rebuilding of the Beit Hamikdash and the coming of the Mashiach.

Chag Kasher v’Samayach!