We’re in one of the hippest enclaves of East London and hundreds of people are leaping up and down, singing along raucously to the ‘80s power ballad being blasted out by a triumphant band. This is no ordinary gig, though. Welcome to the world’s fastest growing church.

For the most part, this Sunday morning congregation has been enjoying something that looks a lot like a traditional church service. The addition of a frenzied clapping game, “mini-rave” break-out sessions, and those billboard anthems might be the most immediately obvious differences, but there is another significant departure: this church is a God-free zone.

Founded in London earlier this year, the atheist church is expanding fast. New branches of Sunday Assembly have already been set up in Bristol, England, Melbourne, Australia, and New York City. Next month, Sanderson Jones and Pippa Evans, the church’s founders, will set off on a world tour designed to announce the second wave of godless churches that are opening in Ireland, Scotland, Canada, the United States, and Australia.

The numbers are still small, but the growth has been exponential since the first atheist church service was held in January. The idea is simple: it has all of the community spirit, engagement, and inspiration of a church without any of the religious aspects. Each service has at least one guest speaker, from economists to poets, a moment of reflection and, above all, repeated entreaties to get to know the rest of the people there.

Jones, the face of the burgeoning organization, has been taken aback by the acceleration of interest. He is a tall man with a thick golden beard and long blond hair; he says there are noble aspirations behind the church but concedes that part of its appeal lies in the sheer amount of fun had by the congregation. “We like to say it’s entertaining but not entertainment,” he told me. “We don’t have Heaven or Hell to tempt or threaten people with, so if you want to get people to come, you want them to say ‘this is a good thing, which I enjoy.’”

At a service this month in Bethnal Green, in London’s East End, it was clear that the mass karaoke was a highlight. “’Living On A Prayer’ smashes it so hard,” Jones said. “Or ‘Don’t Stop Me Now,’ everyone is like, ‘Oh, my God,’ I get to sing this at 11 o’clock on a Sunday—and I’m not even drunk!”

The duo at the heart of this quasi-religious network met through work. They are both stand-up comedians, which helps to explain why their twice-monthly London services are so magnetic, and so funny. Their “mind-meld” began on a three-hour drive to Somerset in South-West England, where they were both booked to appear at a small comedy club in 2011. Their conversion took place on the road to Bath.

Evans, 31, whose eyes gleam behind a mess of blonde hair, was a formerly committed Christian whose faith had lapsed. “When I decided there probably wasn’t a God, it made church a lot more awkward,” she told me. She found that she didn’t miss her faith, but she did miss her church. “I always felt like there wasn’t a place to have that same sort of community. I couldn’t get my head around how to do it without offending anyone,” she said.

Jones, meanwhile, had been struck by a flash of inspiration. “I left a Christmas carol service and thought, there’s so much here that I love, it’s just such a shame that there’s something in the middle that I don’t believe in,” he said. By the end of the road trip, the seeds that would grow into Sunday Assembly had been planted.

A few weeks after my first experience at an atheist church service, as news of the world tour and a fundraising drive was announced, and The Times of London published an approving editorial congratulating the charismatic Jones on the emergence of his new church, I began to wonder whether any right-thinking person could really be setting up their own world religion.

Sitting on a wooden stool in a trendy pizza joint in East London, Jones, 32, agreed to outline his plan for global domination. “The dream is a Sunday Assembly in every town, city or village that wants one,” he said. As he enthuses, jokes and extemporizes, it is obvious why he found success as a comedian and performer. Indeed, he is such a consummate salesman that he was chosen to front a series of advertisements in recent years including Colgate, the Eurostar train service and Ikea.

Despite his clear appeal as a leader, Jones plays down any suggestion that the church would develop into a cult of personality. “It’s really nothing to do with me, it’s the idea that is great,” he said. “And it’s certainly not a cult, they split people off from their families and they are not transparent. Neither of which applies to us, although I do realize it never sounds good to be relying on the technical definition.”

When Jones’s father retired, he started to take an interest in genealogy. “I get this e-mail going, ‘I think we’re related to L. Ron Hubbard [the founder of Scientology],’” he said. “On further investigation we’re probably not… Well, he was adopted and we might be related to his adopted family.”

As we discuss the issue of iconic leadership, it’s Jones who brings up the messiah. “The fact that I have a beard means there are a lot of Jesus jokes,” he said. “But I had it first. Obviously, not before Jesus—before Sunday Assembly.”

The gags are nonstop, as is the juddering laugh than ricochets off the restaurant’s exposed brick walls—but Jones is serious about the project. I ask if two comedians starting a church is some elaborate hoax, like Joaquin Phoenix’s hip hop career. “It’s not a joke. It’s fun, it’s funny, but it’s fucking earnest,” he said.

Once he starts to expand on the rationale behind the toe-tapping atheist church services, it’s obvious that he means it. “It’s about thinking about life in a celebratory way, and Pippa and I have been thinking about it a lot more than most, and it’s really great, the more time you spend thinking about how awesome life is, guess what? The more awesome it is,” he explained. “Just being alive; to become conscious that you are alive, and celebrate that, is just as transcendental as anyone’s God.”

At this point, the chef brings our pizza. Much to his consternation, Jones asks for more salt, which he shakes over the pie. “Yeah, I’m probably going to die soon,” he said.

Since that first service held in Islington, North London, in January, the influence of the church started to spread across London immediately. First came affiliated book and philosophy clubs and discussion groups known as the “No-Bible Bible group” or “Life Anonymous” which gave people the chance to share dilemmas or discuss problems. At the most recent service, the congregation brought food parcels which were donated to food banks, which are run by local Christian churches. “A lot of people say, ‘I’ve got a problem with organized religion,’” Jones said. “But, that’s stupid, organization is one of the best things about religion.” One day, he would like to see an atheist network capable of good works and charity on the scale of established religions.

Next, the expansion went international. Melbourne and New York were the first foreign cities to set up branches of the church, but a more ambitious plan is underway. A world tour, which starts on October 22, will include seven stops in the U.S.; in each city a permanent church is intended to live on after Jones and Evans blow through. From Boston to Silicon Valley, via Washington, Chicago, and Los Angeles, they will help host inaugural church services alongside residents who have signed up to lead local branches.

Nicole Steeves, 36, a librarian from Chicago, met Jones earlier this year. She has signed on to help establish a Sunday Assembly in the city and can’t wait for the atheist missionaries to arrive. “I think the tour is bound to be a hit in the U.S. What happens afterward, during the long-term work of community building, is the real mystery,” she told me. “But I have high hopes.”

Church attendance in the U.S.—at around 40 percent per week—is far higher than in Britain where fewer than 2 percent of the population go to an Anglican church service each week. The level of religious engagement will raise different questions for American Sunday Assembly ventures. Jones said they were looking forward to adapting to the new environment. “In the States you’ve got a whole load of people who get how good church is, religious people totally get why you’d go to church, they think it’s weird that people don’t. In Britain we’ve got to convince people,” he said.

Sunday Assembly is not trying to convert anybody to atheism. Everyone is welcome to the services, but Jones said they would not compromise on their beliefs in order to appeal to any specific groups. “The danger of being open to people of all religions, is you can dilute it until it’s like a Coke ad of affirmative sayings with the emotional depth of an Instagram photo with a quote stuck on the front,” he said. “But we love religion, we think churches are great and we love what they do.”

Jones and Evans have received some hate mail, a lone protester showed up to their event in New York, and they were asked to stop holding events in one deconsecrated church on moral grounds.

However the church is viewed in the U.S., Sunday Assembly is expected to continue its experimental expansion plans. “People started writing to us from all over the world saying we would like to have this—the plan was always to help people to set these up, we just didn’t expect it to go so crazy,” Jones said. “We’re developing a system to help people set them up and then we’re seeing if it works.”

Jones’s naturally disorganized disposition has helped to ensure that there is no overwhelming centralized control. Each new Assembly will be run independently with very little supervision. He admitted that means people might take their idea and misuse it. “It’s a fine line, if you had someone starting one up in Brighton and they started being really Islamophobic every week, we need to have a way of saying this is no longer a Sunday Assembly,” he said.

In fact, the Brighton branch is being set up by Anita and Stuart Balkham, a married couple who live in Sussex. I phoned Anita, 31, a clinical psychologist, who was preparing for their first service on Sunday. “It does feel like a big responsibility,” she said. “But I’m not anxious, I’m excited.”

Balkham had been to several services in London before volunteering to open an outpost in a disused church on England’s South coast. She said each Sunday had been different, “the only thing that was consistent for me was that I went to the pub afterwards with a group of people I didn’t know—and I got to know them.”

Allowing the new local churches to head off in whatever direction they want obviously contains inherent risks, but Jones is confident: “I mean, there’s a 12,000-year-old business model.”

For Evans, who works for the church in between stand-up shows, the strength of existing religious networks did not prepare her for the dizzying speed with which an idea they thrashed out on short road trip has been adopted by fellow nonbelievers all over the world. “The big surprise is that this has become an international movement so quickly, we didn’t realize how powerful the Internet was with an idea —so that’s been amazing,” she said. As word of their adventure races around the web, she has one concern: “The only thing I don’t like is when people assume we spend an hour saying religion is stupid and people who go to church are dickheads, because we very rarely do that.”

U.S. and Canada tour dates:New York: Monday, November 4 Washington DC: Wednesday, November 6Chicago: Friday, November 8San Diego: Saturday, November 9Los Angeles: Sunday, November 10Silicon Valley: Monday, November 11Vancouver: Wednesday, November 13