Australia's most senior Catholic cleric on Monday apologised to those who "suffered at the hands" of priests and religious teachers after a turbulent year for the Church.

Sydney Archbishop George Pell said he was shocked and ashamed, following a series of paedophile allegations against priests and claims that they were hushed up.

In his Christmas message, Pell said his heart went out to "all those who cannot find peace at this time, especially those who have suffered at the hands of fellow Christians, Christian officials, priests, religious teachers".

"I am deeply sorry this has happened," he added.

"I feel too the shock and shame across the community at these revelations of wrongdoing and crimes."

Without specifically mentioning child sex abuse, Pell said the hurt caused was "completely contrary" to Christ's teachings.

"We need our faith in God's goodness and love to cope with these disasters, to help those who have been hurt," he said.

Prime Minister Julia Gillard last month ended more than a decade of growing pressure by ordering a royal commission to investigate the responses of all religious organisations, schools and state care to allegations of abuse.

Her announcement came after claims by a senior police investigator that the Church had covered up sexual abuse of children in the Hunter Valley, north of Sydney, to protect paedophiles and its own reputation.

The government in Victoria state is already investigating allegations of sex abuse by the clergy with the Church telling a state parliamentary hearing in September that at least 620 children had been abused since the 1930s.

When Gillard announced the royal commission, Pell welcomed it as an opportunity to help victims, "clear the air" and "separate fact from fiction".

"We are not interested in denying the extent of misdoing in the Catholic Church," he said at the time.

"We object to it being exaggerated, we object to being described as the only cab on the rank. I don't think we should be scapegoated."

Child sex abuse allegations and claims they were covered up have rattled the Catholic Church across the world, particularly in Ireland but also in the United States, Germany and Belgium.