George Pell's conviction of child sex abuse charges has created a "completely unprecedented" situation for Pope Francis and the Australian Catholic community, church observers say.

Key points: Pell's conviction of child sex abuse could carry "enormous implications" for the Vatican

Pell's conviction of child sex abuse could carry "enormous implications" for the Vatican It is expected Pope Francis will remove Pell from the priesthood following the guilty verdict

It is expected Pope Francis will remove Pell from the priesthood following the guilty verdict Australian Catholics are being urged to move past the "Pell period" with new leadership

Former priest and Catholic historian Paul Collins said he believed it was the most serious conviction recorded against a cardinal of Pell's standing in the modern history of the Catholic Church.

"This is a man who has virtually dominated the Catholic Church [in Australia] for the last 20 years," he said.

He said the conviction would have "enormous implications" for the Vatican and the papacy of Pope Francis.

"I think it is true now to say, although it's taken a while to get to this point, Pope Francis does get it about sexual abuse," Mr Collins said.

"He understands that this is a universal problem in the Catholic Church, and it is going to have to be dealt with radically and quickly."

The English editor of French Catholic newspaper La Croix International, Robert Mickens, said the conviction would be "very embarrassing" for the Vatican given Pell's senior role as a financial adviser.

Robert Mickens said Pell would likely be removed from the priesthood. ( ABC News: Lincoln Rothall )

Mr Mickens said Pope Francis gave the cardinal leave of absence to return to Australia and face trial on the charges, but it was unlikely Pell would return to the role.

"If a priest or a bishop or a cardinal is convicted in a court for abusing a child, I think it's very likely that that bishop, that cardinal, would be removed from the priesthood," Mr Mickens said.

He said the Pope had effectively set a precedent with the expulsion of former US cardinal Theodore McCarrick earlier this month, following McCarrick's conviction of sexual crimes against adults and children.

In December, Pope Francis removed George Pell from his advisory council of cardinals, stating that Pell was one of three "more elderly cardinals" whose terms had elapsed.

The Pope recently called 190 bishops and religious superiors to a conference on the abuse of children by Catholic clergy, where cardinals called for a new culture of accountability to punish those who fail to protect their community against predator priests.

Pope Francis recently summoned senior Catholic clergy to a summit on child sex abuse. ( AP: Andrew Medichini, file photo )

Call to move past the 'Pell period'

Mr Collins said he was initially "flabbergasted" by the guilty verdict in Pell's trial, having followed the court hearings closely.

"I think that once I started to get the facts of the case … it started to become much clearer to me then," he said.

"Now I of course accept the decision of the court, and I simply accept the fact that the court has found him guilty."

However, he said there were still some Catholics across Australia who were "not persuaded" of Pell's guilt, despite being aware of the guilty verdict returned by the jury.

"We are in a way, to use an Australian term, gobsmacked by the situation that we find ourselves in," Mr Collins said.

Speaking to ABC Radio Melbourne, former CEO of the Catholic Church's Truth Justice and Healing Council, Francis Sullivan, was shaken by the news of the guilty verdict.

The council was responsible for coordinating the Catholic Church's official response to the Royal Commission Into Institutional Responses to Child Sexual Abuse.

"When you have a cardinal being convicted, it's more than a person being convicted in a way, it's like our whole approach to life has been put through the wringer," he said.

Mr Collins said the latest in a spate of "revelations and crises" for the Australian Catholic community would need to be addressed with strong leadership from the bishops.

"I actually feel, and I feel this very strongly, that our bishops have failed us totally," he said.

"Perhaps one of the reasons why the bishops have been such abject failures in leadership is because of the type of people that Pell has put forward to Rome for appointment to the Episcopate.

"I think it is time for the bishops to stand up and to assume leadership for the church in this country and above all to move beyond, if you like, the 'Pell period' in Australian Catholic history."

More women were also needed in the church's leadership positions in order to improve the organisation's response to child sex abuse, Mr Collins said.

In a statement, the president of the Australian Catholic Bishops Conference, Archbishop Mark Coleridge, said bishops were "shocked" by the guilty verdict.

"The bishops agree that everyone should be equal under the law, and we respect the Australian legal system," Archbishop Coleridge said.

"The same legal system that delivered the verdict will consider the appeal that the Cardinal's legal team has lodged. Our hope, at all times, is that through this process, justice will be served.

"In the meantime, we pray for all those who have been abused and their loved ones, and we commit ourselves anew to doing everything possible to ensure that the Church is a safe place for all, especially the young and the vulnerable."

Editor's note: On Tuesday April 7, 2020, the High Court in a unanimous decision upheld Cardinal Pell's appeal and quashed his convictions on all five charges.