Church of England bishops have overwhelmingly backed a motion calling for a ban on "unethical" conversion therapy for gay Christians.
Being gay is not a sickness or a sin, the church’s General Synod heard on Saturday as it debated and voted on a private member’s motion (PMM).
Christian gay rights campaigner Jayne Ozanne’s motion called on the C of E to endorse a statement branding the therapy "potentially harmful" with "no place in the modern world", signed by professional bodies including the Royal College of GPs and the UK Council for Psychotherapy in January.
The Archbishop of York, Dr John Sentamu, said during the debate: "The sooner the practice of so-called conversion therapy is banned, I can sleep at night."
The vote sends out a strong message to the world that the church does not see homosexuality as a crime, said Bishop of Liverpool Paul Bayes.
He said: "As the world listens to us the world needs to hear us say that LGBTI+ orientation and identity is not a crime.
"LGBTI+ orientation and identity is not a sickness. And LGBTI+ orientation and identity is not a sin.
"We must distinguish between an ascetic and a therapeutic approach.
"In the Church we are certainly called to help one another to conform their lives to Jesus Christ and to live lives of holiness, but we do not need to engage people in healing therapy if they are not sick."
The Synod, currently meeting in York, has in recent years made headlines as the church tries to balance opposing views on homosexuality from its liberal and conservative wings.
The move is opposed by some conservative Christian groups, with one saying people seeking therapy want to "live full, Christian lives, within the natural order which God created".
A majority backed the motion in both the House of Clergy and the House of Laity, while all but one voted in favour in the House of Bishops.
Ms Ozanne, who herself underwent the therapy, told the Press Association it could ruin lives and in some cases drive people to suicide.
Speaking ahead of the vote she said: "I call it abuse. I believe it is spiritual abuse.
"It (sexual orientation) is a very delicate area that only true professionals should be dealing with. And they won’t try to change people’s sexual orientation, they will help them try to deal with it.
"What people don’t understand is that you can enter into this sort of practice willingly because you think it is the right thing to do because you have been told it is what God wants.
"It is only years later that the impact becomes apparent."
The PMM said conversion therapy "is condemned by professionals as being harmful to LGBT people as it is based on a misguided belief that being lesbian, gay, bisexual or transgender is wrong".
It adds: "This leads to increased mental health problems for the LGBT community due to stigmatisation.
"Given that many practitioners are non-medically trained religious leaders, it is imperative that the Church of England is unequivocal in its condemnation of such harmful practices."
The motion was backed by Simon Sarmiento, chairman of LGBTI MISSION, which campaigns for gay rights within the church.
He said those who support the therapy were a small but vocal minority, adding: "They are against the whole concept of flexibility of sexuality or gender."
Andrea Minichiello Williams, a lay member of General Synod and director of Christian Concern, criticised the motion, saying it had been "brought about on a purely emotional basis".
She said: "There are very many Christian counsellors and spiritual directors, as well as vicars and lay pastoral workers, who meet regularly with Christians with same-sex attraction.
"They do so because the person has come to them, and because they want to explore their sexual desires within the framework of the Bible and Christian discipleship.
"They are looking for pastoral and Godly help to enable them to live full, Christian lives, within the natural order which God created."