One of Pope Francis's top advisers acknowledged that the Catholic Church "has made enormous mistakes" in allowing thousands of children to be raped and molested by priests over centuries.
The admission in testimony at an extraordinary public hearing of an Australian investigative commission was made just a few blocks from the Vatican.
Cardinal George Pell testified late on Sunday via videolink from a Rome hotel to the Royal Commission sitting in Sydney.
In the front row of the conference room were two dozen Australian abuse survivors and their companions who had travelled across the globe to be on hand for Mr Pell's testimony.
The lead counsel assisting the commission, Gail Furness, is questioning Mr Pell about current Vatican efforts to address the scandal as well as his past in Australia, including how he dealt with abuse allegations.
Mr Pell asserted at the start: "I'm not here to defend the indefensible. The church has made enormous mistakes and is working to remedy those."
The cardinal said too many legitimate allegations about sexual abuse from credible sources were often dismissed "in scandalous circumstances".