While the leading ex-gay therapy organisation in the United States recently renounced its practices, andPope Francis said it is not his place to judge homosexuals, some Australian churches believe gay Christians need to invite the Holy Spirit to convert them to being straight.

At Ramsgate Community Church in Sydney's south, Reverend Ron Brookman believes he is helping to save souls.

He is the director of Living Waters, a group that says it helps to heal people's sexuality.

Reverend Brookman, who tells Christians that being gay is a sin, was himself leading a double life as a gay man and a Uniting Church minister.

"I've struggled since I was 11 with homosexuality. I was just overwhelmed with lust, with homosexual fantasy," he told ABC's 7.30.

"I underwent a substantial change there that freed me from the secret life and I found a change in my heart and a swing away from my being attracted to men to actually becoming attracted to women, and one particular woman in particular who is now my wife and the mother of my children and, yeah, there's a beautiful transformation."