Pope Benedict XVI has instructed Roman Catholics to pray “in perpetuity” to cleanse the Church of paedophile clergy. All dioceses, parishes, monasteries, convents and seminaries will be expected to organise continuous daily prayers to express penitence and to purify the clergy.

Vatican officials said that every parish or institution should designate a person or group each day to conduct continuous prayers for the Church to rid itself of the scandal of sexual abuse by clergy. Alternatively, churches in the same diocese could share the duty. Prayer would take place in one parish for 24 hours, then move to another.

Vatican watchers said that there was no known precedent for global prayer on a specific issue of this kind. There are about one billion Roman Catholics worldwide.

The instruction was sent to bishops by Cardinal Cláudio Hummes of Brazil, head of the Vatican Congregation for the Clergy. He told L’Osservatore Romano, the Vatican newspaper, that he was acting in the Pope’s name. The Pope wanted Catholics to pray for the “mercy of God for the victims of the grave situations caused by the moral and sexual conduct of a very small part of the clergy”, he said.

Officials said that the prayers were in addition to support for legal action against paedophile priests by their victims and a code adopted two years ago by the Vatican to try to ensure that men “with deep-seated homosexual tendencies” do not enter seminaries to train for the priesthood.

Cardinal Hummes said that the aim was to put a definitive stop to a scandal that had damaged the image of the Church and forced US archdioceses, including Boston and Los Angeles, to pay millions of dollars in compensation to the victims. He said that the scandal was exceptionally serious, although it was probably caused by “no more than 1 per cent” of the 400,000 Catholic priests around the world.

When the paedophile scandal erupted in Boston five years ago, Pope Benedict XVI – or Cardinal Ratzinger as he was then – accused the media of exaggerating the crisis. He later took a tougher stand and was said to have been behind the statement in 2003 by Pope John Paul II to a meeting of American churchmen in which he said: “The abuse which has caused this crisis is rightly considered a crime by society and is also an appalling sin in the eyes of God. People need to know that there is no place in the priesthood and religious life for those who would harm the young.”

When Cardinal Ratzinger stood in for the dying John Paul II at the Good Friday procession of Easter 2005, he stunned the faithful by deploring publicly “how much filth there is in the Church, even among those in the priesthood”. A month later he lifted the legal protection that the Vatican had given to Father Marcial Maciel, the Mexican founder of the Legionaries of Christ, who was accused of sexual abuse of youngsters. Maciel was banned from saying Mass or speaking in public.

However, Cardinal Bernard Law, who was Archbishop of Boston when the scandal broke, was transferred to a post in Rome and remains a respected figure – despite accusations that he did not take strong enough action in dealing with abuse in his diocese.

The Pope, who is preparing an encyclical on the social effects of globalisation, gave a homily at St Peter’s yesterday on the feast of the Epiphany in which he deplored the West’s “search for excess and the superfluous”. He said: “The conflicts for economic supremacy, and the scramble for energy and water resources and raw materials, render difficult the work of all those who strive to construct a more just and united world. We need a greater hope, which allows us to prefer the common good of all to the luxury of few and the poverty of many. Moderation is not only an ascetic rule, but a way of salvation for humanity.”

Church crisis

$660m The amount paid out by the Los Angeles Roman Catholic archdiocese to 500 victims of sexual abuse

$2bn The amount estimated to have been paid out across the US

4,392 The number of priests alleged to have abused children in the US in the past 50 years

10,000 The number of Americans who say that they were abused

100 The number of allegations of abuse made in Ireland between1962 and 2002

21 The number of priests involved

6 of the 21 Irish priests involved died before any allegations were made against them

3,000 The number of allegations of abuse received by the Australian group Broke Rites by 2002

John Jay Report (2004), Times archives