The Occupy movement has become the latest to use the slogan "what would Jesus do?", something that has been questioned by the Archbishop of Canterbury. But where did the slogan come from and is there ever an answer to the question posed, asks Stephen Tomkins.

Like all the most enduring slogans, "what would Jesus do?" has inspired countless rewrites.

There has been everything from political parody - anti-war T-shirts asking "who would Jesus bomb?" - to the beyond parody such as the "what would Jesus eat?" biblical diet plan.

The original question "what would Jesus do?" has been taken seriously by millions of Christian teenagers who have worn it over the last 20 years as a reminder to live their life in the right way. But it's now been co-opted by protesters outside London's St Paul's Cathedral threatened with eviction.

Particularly in the US, but also elsewhere, it's on wristbands, mugs, T-shirts, bumper stickers, necklaces and earrings, though most of those seem rather to defeat the purpose of reminding the owner about anything.

Pastiche and parody What would Jesus cut? - Washington Post headline on national debt debate

What Would Jesus Deconstruct? - a book of postmodern theology by John Caputo and Brian McLaren

What Would Audrey Do? - Hepburn-based style guide by Pamela Keogh

What Would Google Do? - book by Jeff Jarvis

Who Wants Jack Daniels? - T-shirt

Also available, if you know where to look, are WWJD? teddy bears, WWJD? lunch boxes, WWJD? underwear, and WWJD? baby bibs.

The question has a long history. In 1896 the Kansas Congregational minister Charles Sheldon published a novel called In His Steps: What would Jesus do? in which a town is revolutionised when Christians "pledge themselves, earnestly and honestly for an entire year, not to do anything without first asking the question, 'What would Jesus do?'".

Thanks to a mistake by its first publisher, the book was never covered by copyright, so it was sold cheaply by multiple publishers. As a result it has sold 30 million copies, putting it in the top 50 bestselling books ever.

One of its readers was Janie Tinklenberg, a youth leader at Calvary Reformed Church in Holland, Michigan. After re-reading it in 1989, she talked to her youth group about it.

She considered printing T-shirts for them bearing the slogan, but at the time friendship bracelets were all the rage, so she got a local company to print 300. She opted for the abbreviation WWJD. Tinklenberg asked the group to wear them for 30 days, they caught on locally, and more were needed.

Others with more of a commercial eye than Tinklenberg spotted the trend, made their own and took the marketing to the national level. By the time she attempted to register her trademark it was too late.

Image caption The use of WWJD? can be a simple signifier of faith

Today, tens of millions have been sold, and Tinklenberg and her church, like Sheldon, have not profited from their success, but are certainly just glad to have the word spread.

It is unusual for a slogan to take the form of a question. A few others come to mind: "It is. Are you?" from the Independent newspaper, "Where do you want to go today?" from Microsoft, and "Are you thinking what we're thinking?" from the Conservative Party's 2005 election campaign.

It seems paradoxical that this most popular question-slogan emerged from US evangelicalism, which critics and opponents would not necessarily connect with open-minded questioning.

Perhaps, like the popularity of the Alpha Course with its question mark logo, this shows that religion most connects with people when it raises questions rather than when it answers them.

Image caption The slogan has been much adapted over the years

The Archbishop of Canterbury took on this point this week, writing that WWJD?, while a good question, did not represent a simple path to the truth.

"Christians don't believe that Jesus is there just to give us a good example in every possible human situation," he noted.

For Conrad Gempf, a US evangelical who teaches the New Testament at the London School of Theology, as well-meaning as it is, WWJD? is the wrong question.

"When we look at what the early church did in the Bible," he says, "they didn't copy Jesus. They did what Jesus told them to do. Jesus spoke in parables, his disciples didn't - they preached about him and they told it straight. They didn't walk on water. Jesus didn't tell us to do what he did, he told us to do even greater things."

There are other potential problems with the simple-sounding question. Can we really know WJWD?

The life of a first century Judean carpenter, let alone messiah, is hard to compare to that lived by western teenagers today. "There was never a time when it was appropriate for Jesus to play the saxophone. But there may be a time when it's exactly the right thing for you to do. That bracelet will mislead you," Gempf suggests.

Moreover, the Bible offers very little detail about Jesus's daily life when he wasn't preaching or performing miracles. And what little it does tell us defies all expectations - hanging around with prostitutes and trashing the temple. Is that the kind of behaviour church youth leaders want to encourage?

Sarah Wynter, editor of Youthwork magazine, suggests that the question isn't the whole point of the wristband anyway.

"Teenagers are looking for a way to demonstrate they belong to something," she says. "They might not feel comfortable talking about what they believe, they might still be working some of it out. But wearing a wristband is something they feel they can do to make some kind of a stand."

"What's good about it," says Gempf, "is that it does get people asking a question about what they're doing, looking at it from another perspective. Most people don't ever do that. But the right question is: what did God create me to do?"

WDGCMTD? isn't quite so catchy of course.