By Malcolm Foley

Last updated at 19:11 12 February 2007

Jonathan Edwards, the Olympic champion who once refused to compete on a Sunday, has quit as presenter of the BBC's long- running religious programme Songs Of Praise because he is no longer convinced of the existence of God.

He will make his penultimate appearance tonight as a man deeply troubled by the collapse of his Christian faith, the driving force of his life since his childhood in Devon, where his father was vicar of a parish in Ilfracombe.

A close friend explained: "Jonathan felt he had to leave Songs Of Praise as he felt profoundly uncomfortable doing the programme with the way he now feels."

Edwards's family has been devastated by his crisis of faith, especially his wife Alison, the daughter of an evangelist from the Hebrides.

"Jonathan has not hidden any of his feelings from those closest to him, but it has not been easy for Alison to come to terms with it,' added the friend.

Yet the family has had time to absorb the impact of Edwards's extraordinary change of heart.

His faith, I can reveal, has been under threat ever since he retired in 2003, still holding the world triple jump record.

A family friend said: "Jonathan's identity was tied up with him being an athlete much more than he imagined. He was world record holder and Olympic champion - and it wasn't until he retired he realised how much he depended on that. Not long afterwards, he started to have doubts and uncertainties about his faith. Those doubts have grown louder - and who knows where it will end."

Edwards's torment has been exacerbated by rumours that his 16-year marriage is under threat from the spiritual upheaval and changing circumstances of his life.

While Alison brings up their two sons, Sam, 13, and Nathan, 10, at their six-bedroom home in Gosforth, near Newcastle, Edwards spends some time each month on business in London, where he is a member of the London Organising Committee for the Olympic Games, representing the athletes.

Until last year, he was also a member of Ofcom, the independent regulator for the UK communications industry.

For convenience - and as a financial investment - Edwards has bought a flat near Westminster. Last week the flat and his home in Gosforth were besieged by journalists seeking to confirm rumours that his loss of Christian conviction had led him into the path of temptation.

Another friend of Edwards insisted: "Jonathan is adamant that their marriage is fine and he has nothing to hide."

Edwards has never considered himself famous. Yet the reality is that he was placed on a pedestal as a champion of the Christian cause from the moment he found unexpected stardom at the World Athletic Championships in Gothenburg in 1995. The world triple jump record he set there of 18.29 metres - making him the first man to jump over 60 feet - remains unbroken.

Edwards had already gained major attention four years earlier when he declined to compete at the 1991 World Championships as his event was scheduled for a Sunday and he refused to participate on a day he reserved exclusively for worship.

Later, he rescinded that decision. And his world was turned upside down after his triumph in Gothenburg when 1,000 people awaited his return at Newcastle Airport. Five months later, he won the BBC Sports Personality of the Year .

By the time he climaxed his career with a gold at the Sydney Olympics in 2000, at the age of 34, he was assured of millionaire status. But humbly, he never ceased to remind his audience that his talent was a gift of God.

His charm and intellect - he graduated in physics from Durham University - brought him swift recognition from broadcasting companies. His future looked golden, with clear indications that he would be fast-tracked into broadcasting both sports programmes and religious ones, too.

Six years ago, he was made a Commander of the British Empire and last year he received honorary doctorates from Exeter and Ulster universities.

As Edwards's biographer, I have seen a fragility to his character that he is competent at disguising in public. He lived to honour God, no question.

He has a deep, theological comprehension of the Bible, making his spiritual meltdown even more unlikely. Even so, in the midst of his crisis of faith, Edwards will be accompanying Alison and their sons to their local church this morning. "They still go to church as a family,' explained a friend.

But throughout his medal-winning days as an athlete, Edwards always confessed to one abiding fear. "I always believed success would be the biggest challenge of my faith,' he said.

And so it has proved. Last night Edwards, determined to protect his family, politely rebuffed all enquiries.

"I am going through a difficult period, and one deeply personal to myself and my family and I have no wish to comment,' he said.