Editor of gay magazine Attitude, Matthew Todd, says the church should be 'begging for forgiveness' over its persecution of gay people.
In his blog on the Huffington Post website, Todd slams the church for 'ruining' the lives of countless gay men and women.
He says his personal experience of Christianity has left him needing counselling and says he is 'enraged' by the Anglican and Catholic churches' opposition to gay marriage in the UK.
'It should be begging forgiveness from society because of the LGBT people whose lives it has diminished over the millennia,' Todd wrote.
He added: 'In 2012, as the social fabric of this country is feeling more and more unstable, the church has created a fierce battle over something that will not harm, hurt or even affect anyone except the couples who wish to marry.
'In doing so it has again shown itself as being run by sexually obsessive, hard hearted, fear mongers. I pray their God forgives them. A generation will not.'
To celebrate Attitude's 18th birthday, the latest issue of the magazine features interviews with Tony Blair, David Cameron and Daniel Radcliffe, as well as openly gay soldier and Iraq war veteran James Wharton, who features on the front cover with his civil partner.
Todd says the magazine shows the reality of gay relationships and claims the church should be providing young LGBT people with 'understanding, love and support' not condemnation.
'It may sound brushoffable but you try growing up being told that you may be a threat to society,' Todd wrote.
'For many, the words do sink in. We know that adult gay people have higher rates of depression, suicide and anxiety - not all, but significantly higher numbers - and it is because of the damning cultural atmosphere whipped up by these leaders, who are truthfully leaders in nothing but hypocrisy, and in the Catholic Church's case, the massive global sexual abuse of children.
'Really, enough is enough.'