The big white truck from the Capital Area Food Bank will be parked outside a Silver Spring high school tonight and tomorrow, slowly filling with bags of groceries brought by Jewish worshipers on their holiest day of the year.

On Sunday, the truck was at Temple Sinai in Northwest Washington, where hundreds of Jewish families offered piles of pasta, peanut butter and other nonperishables to stock the shelves of those in need. Later this month, the truck will head to B'nai Shalom of Olney, to pick up another 1,700 or so pounds of donated goods.

For many Jews, collecting food for the needy has become an important part of observing the High Holidays, a 10-day period of reflection and repentance that began last week with Rosh Hashanah, the Jewish New Year, and will conclude with the Day of Atonement, or Yom Kippur, which begins this evening and ends tomorrow at nightfall.

Some area congregations hand out empty grocery bags on Rosh Hashanah and ask worshipers to fill and return them by Yom Kippur, a holiday of fasting and prayer spent mostly in the synagogue. Others collect bags of food from parents dropping their youngsters off at Sunday morning religious school or accept donations throughout the weeklong holiday of Sukkot, which this year starts Oct. 17.

The food that is collected is distributed to needy families by the food bank's 700 partner organizations: soup kitchens, food pantries, day-care centers, senior centers and after-school programs, to name a few.

Many synagogues also encourage congregants to donate money to Mazon, a Jewish anti-hunger organization.

From the pulpit, rabbis preach about the importance of charity in connection with Yom Kippur, in addition to abstaining from food and drink, seeking forgiveness for wrongdoing and asking God for health and sustenance in the year ahead.

"Not only are we doing the introspection that the holiday demands of us, not only are we atoning for the sins of the last year, but one way that we can make amends is by recommitting ourselves to improving the world around us," said Rabbi Fred Reiner of Temple Sinai, which combines its food collection with a walk to support efforts to end homelessness.

He and others involved with the food drives said they offer meaningful symbolism for both Yom Kippur and the upcoming festival of Sukkot, a harvest celebration that also commemorates the Biblical years of wandering in the desert and dwelling in temporary huts.

"This is an opportunity to help those who are always hungry, on the day and in the season that we are hungry," said Adam Zeren, youth director at B'nai Shalom, which began participating in the food drives last year. "Also, as we are gathering in our harvest season, it's our opportunity to harvest some food for those in need."

Although charitable giving, or tzedakah, is emphasized throughout Jewish tradition, the specific practice of donating food on the High Holidays is a fairly modern innovation that has been embraced mostly by Conservative, Reform and Reconstructionist congregations.

Orthodox synagogues and schools tend to collect food for the poor in the spring, before the holiday of Passover, a time when observant Jews empty their homes of bread and other leavened foods. Jewish law explicitly requires giving to the poor just before Passover and on the high-spirited holiday of Purim, which usually falls in February or March.

But those who are filling grocery bags this time of year say the effort fits nicely with the more sacred aspects of the holiday, helping them to connect the spiritual with the practical.

Rabbi Marc D. Israel, education director at Ohr Kodesh Congregation in Chevy Chase, noted that the Yom Kippur liturgy lists charity as one of three main paths -- along with prayer and repentance -- to divine pardon.

"Sure, it's secular, but it is part of how you think about starting off the new year and becoming a better person," said Monica Gourovitch of Bethesda, who dropped off food at Temple Sinai with her husband and 5-year-old twin boys.

More than two tons of food has been collected on Yom Kippur each of the past five years through Am Yisrael, an organization that offers High Holiday services in the auditorium of John F. Kennedy High School in Silver Spring.

Rabbi Bob Sacks, who leads the worship services for as many as 800 people, said volunteers from a Boy Scout troop ferry grocery bags to the truck, so that those attending the services, many of them elderly, do not have to.

At Temple Sinai on Sunday, congregants filled collection bins throughout the morning, piling bags of organic rice and pasta from Whole Foods Market atop canned goods from Safeway and healthy cereals and snacks from Trader Joe's.

"Part of what it means to be Jewish is to be connected with the community and to serve the community," said Victoria Bor of Chevy Chase, a member of the synagogue's social action committee. "It's part of our moral obligation."

At Temple Sinai, Rabbi Fred Reiner, above, leads a walk to support efforts to end homelessness. Below, Victoria Bor, right, watches Alice Howard, 12, and her father, Hugh Howard, drop off food-drive donations.Laura Kumin, left, and Victoria Bor accept donations for the food drive at Temple Sinai in Northwest Washington.