The Church of England bishop in charge of worship says services are dire, incompetent and owe more to entertainment than spirituality.
The Bishop of Salisbury, the Rt Rev David Stancliffe, delivers the broadside in a book for which the Archbishop of Canterbury, Dr Rowan Williams, wrote the foreword.
Bishop Stancliffe's criticisms are particularly telling because he is the chairman of the liturgical commission, the body responsible for the Church's prayerbooks.
"I mind a lot about worship, and wonder at the quality of what is offered in some places in this most important area of the Church's life," he says in God's Pattern.
"In an age when the standards of public performance are so high, how do worshippers manage to keep on going to church faithfully when the way worship is prepared and offered is often so dire, when it is frequently confused with entertainment, and when it is led by those who apparently have no idea what they are doing or professional competence in doing it?"
Bishop Stancliffe enthuses about a service he attended in France during which the congregation moved around the church praying and singing hymns.
"That would be a novel experience to those used to an English parish church, where as a visitor you are often given a bewildering clutch of books and leaflets and shown to a pew [though these days the verger rarely shuts the pew door behind you!].
"All the same, it is rather like being shown to a seat in the cinema; once you're there, its yours and you stick to it."
In the middle of "the clutter of managing different books, finding a place, listening to interminable notices and getting up and down as choirs, clergy and whoever processes in", the essence was lost.
Criticism of services is not new, but rarely has it come from so senior an authority. Ship of Fools, a tongue-in-cheek Christian website, has carried anonymous reviews of services for several years.
While many entries are largely positive, some are cutting. One reviewer of a Devon parish awarded the church only three marks out of 10 after complaining about the uncomfortable pews and the confusing worship.
"The service was not offensive, but neither was it particularly inspiring. It was just 'there'."
The website also runs a lively correspondence from churchgoers irritated by organists who play theme tunes from the Flintstones or Blackadder during services.
Dr Williams is known to be concerned about the quality of the education of many of the clergy after a recent official report said that many were theologically illiterate.
One senior clergy member of the General Synod said: "The astonishingly poor quality of services is directly related to the dumbed down training that clergy are given in theological colleges compared to a generation ago.
"It's DIY religion. Clergy make it up as they go along because they don't know better. I am constantly horrified at the abysmal preaching, and the liturgy is even worse."