An Exeter vicar has warned the Church of England could be extinct in less than 40 years as ageing worshippers die.
The Reverend Simon Austen, of St Leonard's Church, said figures showed the average age of Anglican churchgoers has increased by around 20 years over the past two decades to above 60.
He predicted that if the pattern continued the Church would struggle to exist by around 2050, and described the situation as "concerning".
He said: "You might say it's very 'doom and gloom', which it is, but that's a worst case scenario. All the research over the past 20 years shows a huge decline; and that the pace of the decline is slowing, but the decline is still there."
Speaking to members of his 650-strong congregation, Rev Austen said parishes were "increasingly" joining together as they faced challenges of generating enough money to pay clergymen and to maintain ancient buildings.
He added that, although there were "pockets of life and hope", some churches had "no young people whatsoever".
Rev Austen, 47, who has been ordained for 20 years, said: "The next five years are going to be crucial. The gospel doesn't change, but we must think creatively about new ways to communicate this timeless message."
His warning comes after the Bishop of Truro, the Right Reverend Tim Thornton, said "radical changes" were needed to halt the Church's decline.
Rev Austen also warned that the Church may split over internal disagreement on issues of human sexuality.
According to a motion passed in 1987, the Church's official position on sexuality is that intercourse outside marriage, including homosexual acts, is "to be met with a call for repentance".
A statement released from a College of Bishops meeting in September included an objective for those with differing views of sexuality to "live together" and "share together a place of common baptism and faith".
But Rev Austen claimed a "significant proportion" of orthodox believers would not be able to accept that there were two "equally valid" views for Christians to hold.
He said: "It would be impossible for the Church of England to continue in its present form if one part of it preached repentance and the other preached acceptance in this area. It would, in effect, be a different gospel, re-defining that which relates to salvation.
"The most likely scenario will be either an attempt at two integrities, or a managed separation of the orthodox and the revisionists."
Rev Austen admitted that many gay people in recent years had felt "unwelcomed and unloved" by Christians.
He stressed that there should be a distinction between attitudes towards sexual orientation and sexual behaviour.
He said: "Same sex attraction is no different to any other attraction someone might have. The issue is holiness not homophobia. How we behave is very relevant, whether heterosexual or homosexual.
"Because we've not been clear historically, we've turned a blind eye to sin and have not treated those struggling with same sex attraction well enough. For that we must hold up our hands and repent.
"We must stand firmly alongside such people under what is a very fast moving change in our culture and church on these very issues."
