Looking for His glorious appearing! Titus 2:13

The admission leaves the Church in disarray and will have a devastating effect on its attempt to get its message across.

Cardinal O’Brien was the most high-profile and outspoken opponent of gay marriage in Britain, condemning it as a “grotesque subversion”.

He warned that the plans, supported by the governments in Westminster and Holyrood, would open the way to “further aberrations” and said society “would be degenerating even further than it already has into immorality.”

His comments earned him the title “Bigot of the Year” from the gay rights group Stonewall.

But last night Evan Davis, the BBC presenter, who is gay, posted a message on Twitter suggesting that the Cardinal’s fierce rhetoric might have been a way of suppressing his own “torment”.

In one of the last acts of his pontificate, Pope Benedict effectively sacked Cardinal O’Brien last Monday, just 24 hours after the allegations of “inappropriate conduct” appeared in The Observer.

Although the Cardinal had already tendered his resignation as Archbishop, as he is approaching 75, the Pope took the unusual step of making clear it was to take immediate effect.

The Cardinal also withdrew from the Conclave meeting this month to elect Pope Emeritus Benedict’s successor, in what Vatican historians said was a completely unprecedented move.

In a short statement issued by the Catholic Church in Scotland Cardinal O’Brien made no direct reference to his sexual preferences.

But he made clear that he had initially contested them because of their “anonymous and non-specific nature”.

“However, I wish to take this opportunity to admit that there have been times that my sexual conduct has fallen below the standards expected of me as a priest, archbishop and cardinal,” he said.

It follows the publication of further details of the claims against him, which are being investigated by the Vatican.

The Observer reported that one of the sworn statements said: “He started fondling my body, kissing me and telling me how special I was to him and how much he loved me."

The former priest, who is married, alleges he was a 20-year-old seminarian when the Cardinal, who was then his Spiritual Director, made his advances.

He said that although he was straight, he had remarked at the time that it would have been “easier to get through seminary if you were gay”.

He told the newspaper: “This is not about a gay culture or a straight culture. It's about an open culture.

“I would be happy to see an openly gay bishop, Cardinal, or Pope.

“But the Church acts as if sexual identity has to be kept secret.”

The Cardinal said in his statement: “To those I have offended, I apologise and ask forgiveness.

“To the Catholic Church and people of Scotland, I also apologise.

“I will now spend the rest of my life in retirement. I will play no further part in the public life of the Catholic Church in Scotland.”

Mr Davis tweeted: “I think people who struggle to suppress their homosexual urges find that expressing anti-gay views gives them fortitude in their torment.”