Boston (CNN)--- It's Sunday in Cambridge, Massachusetts, and a rapt congregation listens to a chaplain preach about the importance of building a community.
A few dozen people sit quietly for the hourlong service. Music is played, announcements are made and scholars wax poetic about the importance of compassion and community.
Outsiders could be forgiven for believing this service, with its homilies, its passing of the plate, its uplifting songs, belongs in a church.
If so, it's a church without one big player: God.
Sunday's congregation in Cambridge is a meeting of the Humanist Community at Harvard University and the brainchild of Greg Epstein, the school's Humanist chaplain.
A longtime advocate for community building, Epstein and his group of atheists have begun to build their Cambridge community and solemnize its Sunday meetings to resemble a traditional religious service.
To Epstein, religion is not all bad, and there is no reason to reject its helpful aspects.
"My point to my fellow atheists is, why do we need to paint things with such a broad brush? We can learn from the positive while learning how to get rid of the negative," he said.
For Epstein, who started community-building at Harvard nearly 10 years ago, the idea of a godless congregation is not an oxymoron.
"We decided recently that we want to use the word congregation more and more often because that is a word that strongly evokes a certain kind of community - a really close knit, strong community that can make strong change happen in the world," he said.
"It doesn't require and it doesn't even imply a specific set of beliefs about anything."
Epstein is not alone in his endeavor. Jerry DeWitt, who became an atheist and left his job as an evangelical minister, is using his pastoral experience to building an atheist church in Baton Rouge, Louisiana.
This Sunday, DeWitt's congregation will hold its first meeting as a "Community Mission Chapel."
"When you become a part of this congregation, this community, you are going to become part of a family," DeWitt told CNN. "There is an infrastructure there for you to land in. There is going to be someone there to do weddings and to do, unfortunately, the funerals."
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Sunday school for atheists
As members of the Cambridge congregation file into a wood-paneled classroom at Harvard, singer Shelley Segal greets them with a few songs from her latest recording, called simply, "An Atheist Album."
Taking a hint from the theme of the event, Segal strums on her guitar and belts her song, "Gratitude."
"I don't believe in a great power to say thank you to," Segal sings. "But that won't take away from my gratitude."
Harvard's humanist chaplain Greg Epstein leads an atheist gathering.
After the music, Epstein offers a few words of greeting before the meeting gets to its heart: a discussion about compassion.
A four academics and a journalist discuss the effects of religion on raising children and their ideas about compassion. Congregants listen intently, some even taking notes.
Each service has a message -- compassion, evolution or acceptance - after which congregants engage in a lengthy discussion.
Before the main event, kids are invited to what some parents refer to as "Sunday school," where Tony Debono, a biologist Massachusetts Institute of Technology, teaches the youngsters about evolution, DNA and cells.