Accusation: Bishop Michael Nazir-Ali claims radical Islam is filling the moral vacuum left by the decline in Christian virtues

The collapse of Christianity has wrecked British society, a leading Church of England bishop declared yesterday.

It has destroyed family life and left the country defenceless against the rise of radical Islam in a moral and spiritual vacuum.

In a lacerating attack on liberal values, the Right Reverend Michael Nazir-Ali, the Bishop of Rochester, said the country was mired in a doctrine of 'endless self-indulgence' that had brought an explosion in public violence and binge-drinking.

In a blow to Gordon Brown, he mocked the 'scramblings and scratchings' of politicians who try to cast new British values such as respect and tolerance.

The Pakistani-born bishop dated the downfall of Christianity from the 'social and sexual revolution' of the 1960s.

He said Church leaders had capitulated to Marxist revolutionary thinking and quoted an academic who blames the loss of 'faith and piety among women' for the steep decline in Christian worship.

Dr Nazir-Ali said the ' newfangled and insecurely founded' doctrine of multiculturalism has left immigrant communities 'segregated, living parallel lives'.

Christian values of human dignity, equality and freedom could be lost as the way is left open for the advance of brands of Islam that do not respect Western values.

The Bishopric of Rochester is one of the ten most powerful positions in the Church of England.

Dr Nazir-Ali's attack on the decline of Christianity appears to put him in the opposite corner to the Archbishop of Canterbury, Dr Rowan Williams, and many of his fellow bishops.

But he holds some views in common with the Church's other widely-heard and popular prelate, Ugandan-born Dr John Sentamu, the Archbishop of York.

Over the past six months, Dr Nazir-Ali has made a number of criticisms of Islam and its influence.

Among them have been charges about the spread of no-go areas for non-Muslims and worries over the impact of new mosques.

Last weekend he was one of just three bishops who backed a move in the Church's parliament, the General Synod, to encourage the conversion of Muslims to Christianity.

His latest attack once again criticises Dr Williams's backing for sharia law, saying that 'recognising its jurisdiction in public law is fraught with difficulties, precisely as it arises from a different set of assumptions than the tradition of law here'.

Dr Nazir-Ali detailed his arguments in an article in the newly-launched political magazine Standpoint.

The bishop, himself an immigrant from Pakistan in the mid-1980s, admitted that he might be thought the least qualified person to discuss British identity. But he quoted Kipling: 'What should they know of England who only England know?'

The bishop said 'something momentous' had happened in the 1960s. He quoted historians who point to a cultural revolution in which women ceased to uphold or pass on the Christian faith and to the role of Marxist revolutionaries.

Dr Nazir-Ali pointed with approval to a finding that 'instead of resisting this phenomenon, liberal theologians and church leaders all but capitulated.

Criticised: Archbishop of Canterbury Dr. Rowan Williams has controversially backed sharia law

He said: 'It has created the moral and spiritual vacuum in which we now find ourselves.' In the place of Christianity there was nothing 'except perhaps endless self-indulgence'.

The bishop said the consequences were 'the destruction of the family because of the alleged parity of different forms of life together, the loss of a father figure, especially for boys, because the role of fathers is deemed otiose, the abuse of substances (including alcohol), the loss of respect for the person leading to horrendous and mindless attacks, the increasing communications gap between generations and social classes - the list is very long.'

Another result, he said, was that immigrants had been welcomed, not on the basis of Britain's Christian heritage, to which they would be welcome to contribute, but by the 'newfangled and insecurely-founded doctrine of multiculturalism'.

The bishop warned that views not founded on Christianity would not produce the same values. 'Instead of Christian virtues of humility, service and sacrifice, there may be honour, piety, the saving of face, etc'.

He questioned what resources were available for an ideological battle against radical Islamism, saying 'the scramblings and scratchings around of politicians for values which would provide ammunition' were hardly adequate.

Born into a Roman Catholic family in Pakistan, the young Michael Nazir-Ali converted to Anglicanism at the age of 20.

As a young man, he suffered rough treatment of the kind regularly handed out to Christians in a country where failing to follow the official religion can sometimes end in murder.

He moved to Cambridge to study theology and then returned as a priest to Pakistan before being brought to London in the 1980s to serve as an assistant to the then Archbishop of Canterbury, Dr Robert Runcie.

He is one of the bishops who has been called on by the Prince of Wales to give advice on Islam.

However, Dr Nazir-Ali does not share the prince's enthusiasm for Islamic values. He has warned Charles to give up his hope of being 'defender of faiths' because of the incompatibility of different beliefs.

Dr Nazir-Ali has accused Muslims of promoting double standards by looking for both 'victimhood and domination'; he has called for powers for officialdom to remove veils from Muslim women for security reasons; and he has warned repeatedly over the dangers of extremism.

In particular he has called on Islamic leaders to allow Muslims to abandon their beliefs and adopt other religions.

Dr Nazir-Ali has spoken up for an estimated 3,000 Britons under threat of retaliation for giving up their faith and he has condemned Islamic states that maintain the death penalty for apostasy.

His outspokenness has put him in the vanguard of opposition to hardline Islamism and made him one of the highest-placed enemies of the gay rights movement.

He angered the Archbishop of Canterbury by threatening to boycott this year's Lambeth Conference of Anglican bishops from around the world.

He has criticised civil partnerships and opposed the extension of IVF treatment to single women and lesbians.

Dr Nazir-Ali has much in common with the Archbishop of York Dr John Sentamu. Unlike him, however, he does not have a populist touch.

This may have contributed to his failure to win the post of Archbishop of Canterbury, for which he was once considered a leading candidate.

The 58-year-old bishop has now remained in Rochester for nearly 14 years.