On Sept. 11, 2001, Atlanta native Michael Knopf had been in New York less than two weeks.
The college freshman, a student at the joint program run by Columbia University and the Jewish Theological Seminary, was in Hebrew class during those fateful moments when the towers were struck.
When class recessed for five minutes, the students learned only that the World Trade Center had been hit by a plane, some nine miles from where they were sitting. The teacher, an Israeli, insisted that the class continue, that terrorists must not be allowed to disrupt daily existence.
"I had no conception of the magnitude of the devastation until I saw the second tower collapse on TV," said Knopf, now a newly ordained rabbi who recently became the assistant rabbi of Har Zion Temple in Penn Valley.
"It wasn't real to me until I started hearing the ambulances and police cars. I remember smelling the smoke, all the way up on 120th street," he said.
A decade later, he was tasked by his new congregation with helping to organize an interfaith memorial gathering that's planned for 3:30 p.m. on Sunday at St. Luke United Methodist Church in Bryn Mawr. (Muslim, Christian and Baha'i congregations are taking part. Beth Am Israel in Penn Valley is also a co-sponsor. )
It's one of many local events slated over the weekend to commemorate the 10th anniversary of the Sept. 11 terror attacks, the deadliest in American history. Jews across the region are planning to take part in an array of interfaith gatherings, synagogue programs and community service projects.
Though Knopf knows that he cannot compare his experience with those who lost loved ones or escaped the World Trade Center or Pentagon attacks, he said that the memory of the harrowing trauma remained with him as he considered what such a memorial gathering might accomplish.
"It is something that is present in my mind, now having grown up in a post-9/11 world. It is very much a part of who I am," he said, adding that he hopes the program will demonstrate "cooperation and common vision and common hope in different religious traditions."
Some of the regional events will recall the loss of life in a wider communal context. Others will do so in a Jewish space, perhaps highlighting the contradiction that, while not a specifically Jewish tragedy, the event seemed like it was ripped from the pages of Jewish history and also evoked the terrorist attacks that have plagued Israel for decades.
Several rabbis noted that, even if their congregation didn't have anything special planned for Sunday, it would be impossible to get through Shabbat services this week without at least referencing the tragic events.
The most high-profile events have been in the works for months and are being organized by the City of Philadelphia, the National Constitution Center and the Religious Leaders Council of Greater Philadelphia in conjunction with the Interfaith Center of Greater Philadelphia.
The Religious Leaders Council prayer gathering is slated for 4 p.m. at the Arch Street Friends Meeting House. At 5:30, the city will hold its event on Independence Mall. The Constitution Center is having programming throughout the day.
Rabbi David Straus, an original co-convener of the council, said that he hopes the official events offer area residents of all faiths "a chance to gather in prayerful reflection to remember what happened on that day; to remember and honor those who were killed."
Straus, the religious leader of Main Line Reform Temple-Beth Elohim and president of the Jewish Community Relations Council, said the interfaith prayer gathering will also provide an opportunity "to join with others as we commit to building community based on justice, tolerance, understanding and compassion -- a more perfect union."
For some, the day won't be marked by attending memorial services but by performing a service of some kind.
The anniversary date provided a quandary for the Jewish Relief Agency, which distributes monthly packages to more than 3,000, low-income individuals. Director Amy Krulik said that the Sunday distribution dates are selected more than a year in advance. In planning this year's schedule, she considered Sept. 11 and wondered: Was it appropriate to ask volunteers to come out on such an occasion? Wouldn't many want to attend memorial events?
In the end, Krulik decided that helping others was the perfect way to spend a few hours on such an anniversary. She later felt validated when President Barack Obama declared Sunday a national day of service.
"They are going to be able to do something to mark that day, to say, 'Even now, 10 years later, we are still going to do things to make our community a better and stronger place'," she said.
On Sept. 16, 2001, JRA had actually planned to mark its one year anniversary. The distribution went forward, but the mood was beyond somber. Sen. Arlen Specter had been slated to speak to the group and he kept his appointment.
This Sunday, Krulik said, volunteers will pause once again to hear the reflections of Specter, now a former senator practicing law.
Rabbi Eric Yanoff of Adath Israel, a Conservative synagogue in Merion Station, noted that, in many congregations, Sunday happens also to be the first day of Hebrew school.
He pointed out that few, if any religious school students are old enough to remember the events; many were not even born yet. The challenge for educators, he said, is crafting a poignant approach that is age appropriate and not overly traumatic.
Teachers for the older grades, he said, will highlight several stories from that day that were true models of self-sacrifice and heroism. For adults, the congregation is also planning a brunch discussion.
Also on the educational front, the Foreign Policy Research Institute -- though not a Jewish organization, it is run by a former Hebrew school teacher -- is planning two web seminars aimed at high school students. More than 160 classes around the country signed up for two sessions on Sept. 8 in which students question experts about the historical significance of the events, as well as what they mean today.
FPRI acting president Alan Luxenberg, who for years taught at Congregation Adath Jeshurun in Elkins Park, said the program offers students the chance to better understand one of the seminal moments of their lives and some of the changes that have resulted.
"They may not have been there, but they certainly have been there for the aftermath of the event," he said.
In a Jewish context, does the 10th anniversary have any particular significance? After all, when traditionally observing the yahrzeit of a loved one's passing, no distinction is made liturgically between, say, the ninth anniversary and the 10th anniversary.
Knopf, the Har Zion assistant rabbi, acknowledged that the number 10 doesn't have the same resonance in Judaism as seven or 18. But, he noted that each letter of the Hebrew alphabet is assigned a numerical value. In the case of 10, it's the letter yud.
He pointed out that yud is the first letter of the unpronounceable name ascribed to God. Kabbalists, he said, taught that "if God permeates the world and our task is to repair the world, it is our task to help put God back together."
So, he suggested, the 10th anniversary signifies that the work of mending what's been broken has begun.
"We have come a long way since the moments of the attacks and we still have a long way to go," he said. The destination, he added, is "a world where no one has to live in fear of something like this again."