29/02/2016 8:04 AM AEDT | Updated 15/07/2016 12:51 PM AEST

Cardinal George Pell Admits Catholic Church Made 'Enormous Mistakes' With Paedophile Priests

SYDNEY -- Cardinal George Pell has told a Royal Commission the Catholic Church has made "enormous mistakes" and criticised how one paedophile priest was moved from parish to parish in Victoria.

But the man now in charge of the Vatican’s finances denied knowledge of paedophile priests in the archdiocese of Ballarat when he was a priest and a bishop’s advisor.

In the opening hour of testimony, Pell said the church had made "enormous mistakes and is working to remedy those” in relation to its handling of child sexual abuse.

"I’m not here to defend the indefensible," he said to the full room of abuse survivors, journalists and supporters of the church.

“The church has made enormous mistakes and is working to remedy those, but the church is in many places, certainly in Australia, has mucked things up, has let people down. I’m not here to defend the indefensible.”

The Cardinal is giving evidence to the Commission over the next few days into how the Catholic Archdiocese of Melbourne and Catholic Church authorities in Ballarat responded to wide-spread abuse.

The opening hour of testimony was characterised by moments of complete clarity when Pell, 74, recounted details of his time a priest in Ballarat in the 1970s.

During that time Pell was a consulter -- someone who gives advice to bishops, including the placement of priests. Pell was a consulter for Bishop Ronald Mulkearns at a time when priests were abusing children in Ballarat.

These moments, however, were interspersed with an inability to remember certain events. Pell responded to several questions by saying, "My memory might be playing me false", "I don't have perfect recall", "I can't remember exactly what I heard when" and "I'm having a senior moment".

The commission probed him about numerous priests and brothers, including-- Monsignor John Day, Father Paul David Ryan and Gerald Ridsdale, one of Australia’s worst paedophiles.

Pell said he could not recall information that Paul David Ryan, a pedophile priest, was sent away for treatment for his sexual behaviour in 1977. He also said he had no recollection of rumours Monsignor John Day was taking children on car trips and abusing them in 1971.

He said the way pedophile priest Gerald Ridsdale had been dealt with was a “catastrophe for the victims and an catastrophe for the church,” and said Mulkearns should have taken actions against him earlier.

“He was given chance after chance, shifted him around and initially at least, trusted excessively in the possible benefits of psychological help,” he said.

“I think in one case he was being treated for anxiety, not to help him with his paedophilia.”

The Cardinal was also asked about offending by a number of Catholic Brothers at St Paul's Technical school, St Patrick's College in Ballarat and the St Alipius School.

He agreed there were teachers aware of it, the principals of both schools were aware of it, that a number of parents and he did not dispute that Bishop Mulkearns was aware of it.

"You'd agree ... that the knowledge of the sexual offending by Christian Brothers at St Alipius School and St Pat's School was known by a significant number in the community," Furness asked.

The Cardinal replied: "I would agree that it was known to all the people whom you've mentioned and they do constitute a significant number."

Pell was read a statement form one border at St Pat's in 1973, who referred to "a survival of the fittest environment," and that children referred to boys being abused as the brothers' "bum buddies."

He said the term had never come to his attention.

Earlier he was asked about another Christian Brother taking boys on bike rides and swimming with them in the nude, and whether it had ever come to his attention and what he thought when he'd heard it.

"It was quite common knowledge," he said.

"Once upon a time in the schools it was not uncommon at all; it was most unusual at that stage and for us, but no improprieties were ever alleged to me."

But he agreed with Furness that it would have been considered "imprudent" at the time.

Now the Vatican’s third highest ranking official and in charge of the city-state’s finances, Pell was granted leave to appear via video link in Australia after the commission earlier this month accepted medical evidence a long-haul flight posed risks to the Cardinal's health.

Counsel assisting the Royal Commission, Gail Furness SC, asked Pell about the consistency of findings by inquiries around the world in relation to the actions of senior officials in the church, and why it was the church operated in such a similar way around the world.

“Unfortunately, original sin is alive and well; the tendency to evil in the Catholic Church too, and sometimes it’s better, sometimes its worse but for good or or ill the church follows the patterns if the societies in which it lives,” he replied.

Shortly before Pell started giving evidence, a cameraman and journalist were allegedly punched and shoved by private security guards surrounding him as he arrived at Hotel Quirinale.

Pell’s office have denied the guards were working for him.