Dr Mike Davidson, a Christian campaigner with a homosexual past, says others, too, can reject what he calls a sin.

“I don’t want to be outrageous,” says Dr Mike Davidson softly – but it is hard to believe him. The 57-year-old Christian counsellor and campaigner has upset a lot of people lately, with his claims that homosexuals can become straight if they get enough help, therapy and prayer. The doctor has been called deluded and his work condemned as “inflammatory, homophobic and harmful”.

The Mayor of London has just banned advertisements that Davidson and his allies planned to put on the sides of buses, declaring: “Not Gay! Ex-Gay, Post-Gay and Proud. Get over it!” They were meant to mirror a campaign by the gay rights group Stonewall, but Boris Johnson pulled the ads after taking offence at the suggestion he saw within them.

“It is clearly offensive to suggest that being gay is an illness that someone can recover from,” said Johnson, who feared “a backlash so intense it would not have been in the interests of Christian people in this city”.

I’m expecting a firebrand. What I get is a gently spoken, slightly stooping man with a South African accent, who lives in a neat detached house in the countryside south of Belfast. His wife, Lynore, brings coffee and chocolate biscuits. They have been married for 32 years, during which time he claims to have been turned away from homosexuality by a combination of counselling, prayer and psychotherapy. He also claims to be able to help others do the same.

Such therapy has been going on quietly in Britain for years, particularly among Evangelicals, but has only recently come to public attention through the efforts of those who oppose it. So is he really suggesting – as they say he is – that homosexuality can and should be cured?

“We don’t consider it a disease,” says Davidson, who works under the banner of the Core Issues Trust. “There are plenty of people who work in a therapeutic context to achieve life goals. There are some people who have tried gay; it doesn’t work for them. It’s not mixing with their life circumstances. They want to move out of it. They deserve to receive professional help that is well trained, well regulated and ethical. That’s what we are trying to achieve.”

His doctorate is in education rather than medicine. Until recently, Davidson was training in psychodrama, which uses role play to address past experiences. However, the British Psychodrama Association has suspended his membership, a decision he is appealing against.

So if not a disease, what does he think gayness is? “I see homosexuality as a normal developmental aberration. Which I know would sound profoundly disrespectful to some people, but that is how I have experienced it.”

That word “aberration” will be offensive to many. What does he mean by it? “I feel the human trajectory, the normal pattern, is around reproduction between a man and a woman. That is the default setting in the human species. But I believe that some people don’t go in that direction. I would say it’s a normal problem.”

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