Cardinal George Pell agreed that putting a sex abuse victim through a legal wringer was un-Christian when he faced a child abuse inquiry in March.
The hearing was the eighth by the royal commission into institutional responses to child sexual abuse.
It was revisiting the well-known John Ellis case to explore Catholic Church legal liability.
Father Aidan Duggan abused John Ellis when he was an altar boy between 1974 and 1979. The impact hit Mr Ellis as an adult and broke him mentally.
He lost his job as a partner in a law firm.
He first went through the church procedure for abuse victims, seeking pastoral care as well as redress for the harm.
When it failed he sued the trustees of the archdiocese and then archbishop George Pell.
In 2004, he lost and what has became known as the Ellis Defence was created – it clarified the church was not a legal entity which could be sued for abuse.
The church still uses the defence when victims come forward, the commission heard.
Dr Pell said he was following lawyers’ tactical advice when he instructed strenuous and vigorous defence of whether Mr Ellis was ever abused.
This led to four days of cross-examination.
The church had accepted the fact earlier.
The cardinal said he wanted to discourage people from suing. He now regretted it.
In the church process Ellis was offered small sums of money, and senior church witnesses told the hearing the archbishop would have been aware of all offers.
Dr Pell said he was not.
At the end of his evidence he read a formal apology to John Ellis without looking at him.
The litigation cost the church $1.5 million, including $568,000 in ex gratia payments to Mr Ellis.
Lawyers and senior church officials from the Sydney diocese were in the witness box for the Ellis hearing.
The chief witnesses were John Ellis and Cardinal George Pell.
Cardinal Pell was asked why he instructed solicitors to dispute the abuse in court when the church had accepted it happened.
He said it was a legal tactic and he thought John Ellis would understand that.
Dr Pell insisted disputing it was not the same as denying it had happened.
The Cardinal also said the court case was an attempt to discourage people from suing the church.
Counsel assisting the commission Gail Furness SC asked if he was telling potential plaintiffs to think twice before litigating the church.
Cardinal Pell: “That they should think clearly, they should consider the advantages in not going to litigation.”
Mr Ellis said Fr Duggan gave him a book about homosexual relationships and he later believed he was homosexual or bisexual.
He was embarrassed and ashamed and for a long while blamed himself.