Pope calls abusive clergy 'tools of Satan'

"The brutality of this worldwide phenomenon becomes all the more grave and scandalous in the church, for it is utterly incompatible with (its) moral authority and ethical credibility," the Pope said in a speech in Vatican City on Sunday.

"Consecrated persons," he continued, "chosen by God to guide souls to salvation, let themselves be dominated by their human frailty or sickness and thus become tools of Satan."

The Pope's speech, delivered at the end of Mass at Sala Regia in the Apostolic Palace, came at the end of an unprecedented gathering of 190 Catholic leaders, including 114 bishops from around the world, to address a clergy sexual abuse scandal that stretches across several continents.

In his wide-ranging speech on Sunday, Francis framed the church's abuse crisis within the wider context of society, even saying that pagans, in history, had "sacrificed children" in rituals.

"We are thus facing a universal problem," the Pope said, "tragically present almost everywhere and affecting everyone. Yet we need to be clear, that while gravely affecting our societies as a whole, this evil is in no way less monstrous when it takes place within the church."

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Dozens of survivors of sexual abuse perpetrated by Catholic clergy have also been in Rome this week to protest and offer testimonies about their experiences.

The four-day summit has included two speeches by the Pope, talks outlining best practices and small-group discussions among bishops.

Francis began the unprecedented summit on Thursday by saying that Catholics are not looking for simple condemnation, but concrete actions.

"In the face of this scourge of sexual abuse perpetrated by men of the church to the detriment of minors, I thought I would summon you," he said, "so that all together we may lend an ear and listen to the Holy Spirit ... and to the cry of the small ones who are asking for justice."

"The holy people of God are looking at us and expect from us not simple condemnations," Francis continued in his opening address, "but concrete and effective measures to put in place. We need to be concrete."

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The bishops have discussed several measures, including a proposal to hold bishops accountable and lift the Pontifical Secret that often keeps abuse victims in the dark about how their church trials are processing. But they did not appear to vote on or immediately adopt any new measures.