It comes from an Anglican vicar rather than Richard Dawkins. The ‘What The F*** Would Jesus Do?’ bumper sticker is a creation of the Reverend Alice Goodman.

Goodman pointed out that she gave Rowan Williams a ride in her car and he didn’t raise an eyebrow. How could she tell – surely they don’t move?

The Venerable John Beer, Archdeacon of Cambridge, reckons ‘Christianity has a long tradition of open debate where people can bring their differing views and share their perspectives.’ I reckon that a vicar who thinks she will stimulate open debate by resorting to a vulgarity, whose overuse has rendered it meaningless, is unhinged.

Rev Goodman: if you really wants to stimulate – not necessarily open – debate, try WTFWMD. M=Mohammed.

From here:

A female vicar yesterday insisted she has not sinned against God by putting an obscene bumper sticker reading ‘WTFWJD’ on the back of her car.

The Reverend Alice Goodman stuck the sticker, standing for ‘What The F*** Would Jesus Do?’, on the back of her red Subaru Legacy – sparking outrage from members of her parish.

But the Reverend insists the sticker is harmless and even the former Archbishop of Canterbury Dr Rowan Williams was happy to accept a lift in her car in the past.

The sign – a play on the Christian motto ‘What Would Jesus Do?’ – has offended some of the worshippers in the Fulbourn and Wilbrahams parish in Cambridgeshire where Dr. Goodman is the rector.

But the American-born vicar, 54, claimed she was simply using an Old English word.

She said: ‘F*** is not a blasphemy, it’s a vulgarity, an Old English word.