People usually think of religion in terms of a lifetime of commitment, but could you learn anything from trying one out for a month?
The call to prayer sounds from Eyup Mosque in Istanbul and local Muslims gather on the marble square outside for prayer. Men on one side, women the other, they crowd on mats for the Friday ritual.
Among them this week though are a few faces looking less than confident about what comes next.
Barbra Taylor, from Hawaii, and Terry Goldsmith, from Bury, Greater Manchester, are two of them. They're not Muslim, but guests for nine days.
This is part of Muslim for a Month - a programme from social enterprise group The Blood Foundation where participants get to "test-drive" a religion.
"Coming away to do this process, some of my friends have questioned it and said, 'Are you crazy? Aren't you going to the enemy camp?'" Taylor says.
"They feel anyone who's even remotely affiliated with the Muslim faith is a terrorist. I just felt this programme is interesting to me - I had an interest in Turkey and also I felt there was a misunderstanding about perhaps the second largest religion in the world."
For Goldsmith it was his changing surroundings at home that inspired the trip.
"One of the things is that there are a large number of Muslim people in the area I live in," he explains.
"I don't really know much about the people and I'd like to learn something of the religion and the culture."
Participants pray, fast, have lectures from Muslim scholars and spend time with Turkish families. Most are here for their first taste of Islam, but some for a deeper understanding of the Sufi culture of Turkey.
H Masud Taj is an architect from Canada, brought up Muslim in India. There were a number of questions about why he needed to become Muslim for a Month.
"My first response was that I was bemused, frankly," he says. "I was bemused that something that we take as sacred as religion could become like a shopping mall - try this out for a month.
"It really seemed a very post-modern phenomenon, but, once here it really envelops you with its own world view so I think it's fascinating."
Like many of the participants, Taj felt that Turkey was the place to hold this course. It may not have worked in other Muslim countries.
There were tougher moments for participants; some women found being separated from the males in the group somewhat jarring. The organisers say this is all part of the experience.
"I mean these are very hot points that often if they're not dealt with can be blown out of all proportion," says Ben Bowler of the Blood Foundation.
"The difference is sticking with that and working through that and certainly there is an element of how women are treated in a religious sense in Islam, which is different from what we would expect in our culture. But this is the point of a cultural exchange - if it was exactly the same it wouldn't be interesting."
Taylor says she's taking home a different outlook, although she won't be pushing it with her friends back in America. The subject's still too sensitive, she says.
"I've really learnt a lot this trip. We've been fully immersed - praying in a mosque, the ladies coming to show us what to do, really it's been a real eye-opener for me in a positive way."
But the organisers say it's been a tough ride. The title Muslim for a Month has put many people off, with some parts of the travel industry refusing to promote it because of the unease surrounding Islam in some quarters.
"Sufi for a month" is going to start running as an alternative and plans for "Sikh for a week" are under way.