Pope Francis has vowed to confront clergy sex abusers with 'the wrath of God' and compared their actions to human sacrifice.
He made the remarks during a mass in the Vatican City to conclude his extraordinary summit on preventing clergy sex abuse.
Francis also pledged to end the cover-ups by their superiors and prioritise victims of this 'brazen, aggressive and destructive evil'.
The Guardian reported Pope Francis, concluded mass by comparing the abuse of children to 'human sacrifice'.
He said: 'Our work has made us realise once again that the gravity of the scourge of the sexual abuse of minors is, and historically has been, a widespread phenomenon in all cultures and societies.
'I am reminded of the cruel religious practice, once widespread in certain cultures, of sacrificing human beings – frequently children – in pagan rites.'
Pope Francis has concluded his extraordinary summit on preventing clergy sex abuse by vowing to confront abusers with 'the wrath of God'
Francis delivered his remarks before 190 Catholic bishops and religious superiors who were summoned to Rome after more abuse scandals sparked a credibility crisis in the Catholic hierarchy and in Francis' own leadership.
And he offered a global review of the broader societal problem of sexual tourism and online p 0 r n o g r a p h y, in a bid to contextualise what he said was once a taboo subject.
The Jesuit pope claimed the vast majority of sexual abuse happens in the family.
But he said the sexual abuse of children becomes even more scandalous when it occurs in the Catholic Church, 'for it is utterly incompatible with her moral authority and ethical credibility'.
'We need to recognise with humility and courage that we stand face-to-face with the mystery of evil, which strikes most violently against the most vulnerable, for they are an image of Jesus,' he said.
Francis summoned the bishops from around the world to the four-day meeting to impress upon them that clergy sex abuse and cover-ups are not just a problem in some countries but a global problem that threatens the very mission of the Catholic Church.
'Brothers and sisters, today we find ourselves before a manifestation of brazen, aggressive and destructive evil,' the pope said.
He offered an eight-point pledge of priorities going forward, calling for a change in the church's defensive mentality and a vow to never again cover-up cases.
Victims, he said, must take centre stage while priests must undergo a continuing path of purity with the 'holy fear of God' guiding the examination of their own failures.
'In people's justified anger, the church sees the reflection of the wrath of God, betrayed and insulted by these deceitful consecrated persons,' he said.
Australian Archbishop Mark Coleridge delivered the homily, pledging to 'bring justice and healing to survivors of abuse,' ITV reported.
He said: 'We will listen to them, believe them, walk with them, we will ensure that those who have abused are never again able to offend, we will call to account those who have concealed abuse.'
The Archbishop of Brisbane added 'we will educate all our people in what safeguarding issues requires' to ensure the 'horrors of the past are not repeated.
He added that 'the Church is a safe place for all, a loving mother especially for the young and the vulnerable'.
Francis summoned bishops from around the world to the four-day meeting. The aim of the summit was to hit-home that clergy sex abuse and cover-ups are a global problem that threatens the mission of the Catholic Church.
He told those at the summit: 'Brothers and sisters, today we find ourselves before a manifestation of brazen, aggressive and destructive evil.
The pope also offered an eight-point pledge of priorities going forward - calling for a change in the church's defensive mentality, while vowing to never again cover-up cases.