By Anita Oh

PHILADELPHIA (CBS) – When the sunlight ends, the Passover celebration begins.

“It’s to celebrate the freedom from bondage when the Jews left Egypt,” said Ralph Schurr of Montgomeryville.

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And at Pumpernick’s Deli in Montgomeryville, a steady stream of customers picked up preparations for the Seder, a ritual feast that marks the beginning of the weeklong holiday.

“There’s chopped liver, gefilte fish, sweet and sour meatballs, potato latkes. It’s a holiday where you’re not supposed to have anything with yeast in it so it’s a lot of specialty cooking,” said owner Jeff Klein. “Preparation started a few weeks ago and in the last three to four days, we probably put in 15-20 hour days.”

The removal of yeast from foods and homes during Passover is to signify that the Israelites had no time for their bread to rise as they made a hurried escape from Egypt.

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It’s a celebration that means much to the Kleins, who own the Jewish deli and offer a full Passover dinner menu on Monday and Tuesday nights, both fully booked.

“Growing up, it meant a lot to me as a kid,” Klein said. “And now as a dad to two girls, the tradition of the holiday means everything to us and being able to help other families celebrate the tradition is the biggest reason why we’re doing it.”

Many say celebrating Passover is even more important this year after recent attacks on Jewish community centers and vandalism at Jewish cemeteries.

“We’re celebrating bad things that happened many years ago and I think it’s interesting that we’re seeing bad things happen still today. I think it’s important that we stick together as a family, as a community, as a religion,” said Samantha Drossner of Blue Bell.

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Passover ends at sundown on April 18.