Retired Pope Benedict XVI has published a controversial analysis on the Catholic Church's clergy sex abuse scandal, blaming it on the sexual revolution of the 1960s and Church laws that protected priests.
The pope emeritus on Thursday also blamed the scandals on a collapse in faith in the West and the "absence of God."
The ex-pope, who retired in 2013, said responsibility for the crises rocking the Roman Catholic Church globally from Australia to Europe lay with the fight for an "all-out sexual freedom, one which no longer admitted any norms."
"Part of the physiognomy of the Revolution of '68 was that paedophilia was then also diagnosed as allowed and appropriate," he wrote in a 6,000-word essay for Klerusblatt, a German monthly magazine for members of the clergy.
Benedict, who was the first pontiff to resign in almost 600 years, said the direct consequence was the "collapse of the next generation of priests in those years and the very high number of laicisations" or priests leaving the Church.
The 91 year old claimed paedophilia "reached such proportions" because of the "absence of God."
The essay immediately raised eyebrows, seeming to interfere with or even contradict Pope Francis' own efforts to confront one of the most critical issues facing the Church.
One church historian called Benedict's essay "catastrophically irresponsible," because it conflicted with Francis' own efforts to lead the Church out of the sex abuse crisis. In his introduction, Benedict said both the Vatican secretary of state and Francis had given him permission to publish it. The Vatican press office confirmed it was written by Benedict.
Benedict in 2013 had said he planned to retire to a lifetime of penance and prayer and would leave Francis to guide the Church.
Some theologians were quick to criticise Benedict's analysis of the causes of clerical paedophilia.
"It does not address structural issues that abetted abuse cover-up, or Benedict's own contested 24-year role as head of the Vatican's powerful doctrinal office," Vatican expert Joshua McElwee wrote in the National Catholic Reporter.
The German ex-pope said the sexual revolution also led to the "establishment" in various seminaries of "homosexual cliques... which acted more or less openly and significantly changed the climate."
He recalled one bishop who "arranged for the seminarians to be shown pornographic films, allegedly with the intention of thus making them resistant to behaviour contrary to the faith."
The Church was first rocked by the child sex abuse crisis in the second half of the 1980s, particularly in the United States, and it has been repeatedly criticised for protecting paedophile priests and its reputation.
US church analysts said the essay, was both flawed in content and problematic on universal church level, exacerbating existing divisions in the Church that have emerged between supporters of Francis and Catholics nostalgic for Benedict's doctrine-minded papacy.
In the essay, Benedict traced the start of the clergy abuse crisis to the sexual revolution of the 1960s, citing the appearance of sex in films in his native Bavaria. He also blamed the crisis on failures of moral theology in that era, as well as church laws that gave undue protection to accused priests.
Benedict wrote that during the 1980s and 1990s, "the right to a defense [for priests] was so broad as to make a conviction nearly impossible."
As Cardinal Joseph Ratzinger, Benedict reformed those laws in 2001 to make it easier to remove priests who abused children. Benedict took a hard line against clerical sex abuse as the Vatican's conservative doctrine chief, and later as pope, defrocking hundreds of priests accused of raping and molesting children.
Francis has blamed the scandal on a clerical culture in the Church that raises priests above the laity.
Villanova University theologian Massimo Faggioli said the essay was thin in its analysis by effectively attributing the scandal to the sexual revolution. He said it omitted key cases, such as the Legion of Christ founder's paedophilia, which began well before then.
"If a pope emeritus decides to stay silent, it's one thing and can be defended. But speaking and telling a tiny part and a very personal version of the story, it's hard to defend," he said on twitter.
"Everything we know in the global history of the Catholic abuse crisis makes Benedict XVI's take published yesterday very thin or worse: a caricature of what happened during in the Catholic Church during the post-Vatican II period – with all its ingenuities and some tragic mistakes," he tweeted.
Church historian Christopher Bellitto questioned if Benedict, who turns 92 next week, was being manipulated by others.
"It is catastrophically irresponsible, because it creates a counter-narrative to how Francis is trying to move ahead," he said. "The essay essentially ignores what we learned."
David Gibson at Fordham University's Center on Religion and Culture agreed with that assessment.
"For a retired pope to try to undo the critical work of a sitting pope and on such a crucial issue seems ... bad," he said.