A judge has ordered that a victim of child sexual abuse should not be forced to pay his abuser's $20,000 legal bill.

Mark Wurth was repeatedly sexually assaulted by his housemaster, Neville Gilbert Betteridge, at the Blue Mountains Grammar School in the 1970s.

Years later he sued his abuser and the Anglican Church, which ran the school, for damages.

The church paid him a confidential settlement and Mr Wurth then offered to withdraw his action against Betteridge.

But as the ABC reported exclusively in April, Betteridge demanded that Mr Wurth first pay his $20,000 legal bill.

Yesterday a NSW Supreme Court judge found Mr Wurth should not be forced to pay the bill.

Justice Ian Harrison said it would a "conspicuous waste of emotional and financial resources" to allow the court case to proceed any further.

He said Mr Wurth had suffered significant stress and anxiety and did not want to go to trial.

"This may be because the prospect of doing so is emotionally difficult for him or because there is no prospect of a successful monetary or financial outcome," Justice Harrison said.

He granted Mr Wurth's application to discontinue the case and made no order as to costs.

"I am relieved that this is over and I don't have to be subjected to any cost claims from Neville Betteridge, a predator," Mr Wurth said.

"However, I was letting Neville Betteridge off any further litigation due to him having no finances, so I have been put though a lot by his legal team in their grubby grab for money."

Mr Wurth was 14 when he was first assaulted by Betteridge.

"He was coming into the dormitory through the infirmary of a night and taking me from my bed back to his room," Mr Wurth told the ABC earlier this year.

"He was a very big drinker. Cigarettes and alcohol were involved every single time."

In 2004, Betteridge was convicted of two counts of indecent assault on Mr Wurth and was given a three-year suspended jail term.

Seven years later, Mr Wurth sued the Anglican Church Diocese and Betteridge in the NSW Supreme Court.

Legal action 'felt very similar' to childhood abuse

After the church settled and he offered to withdraw the case against Betteridge, Mr Wurth was shocked to receive a letter from Betteridge's lawyers, demanding that he pay their client's legal costs.

"I was just [saying] you're joking, you know, like when does a victim pay a perpetrator's costs?" Mr Wurth said.

"Then it got into the legalities of the whole thing and I just found it traumatising again that he's demanding I do that.

"It feels very similar to how I felt when he was abusing me as a kid. I've got no control. I'm just made to do what he says, in effect. There's nothing I can do.

"The settlement I got from the Anglican Church is just getting eaten away. It seems like the settlement was just here to feed the legal profession."

Betteridge's barrister Paul Glisson said his client was entitled to seek costs under part 42, rule 19 of the Uniform Civil Procedure Rules 2005.

"Mr Betteridge has a right to get his costs under the rule, unless the court orders otherwise," Mr Glisson said.

"Mr Wurth has been compensated by the Victim's Compensation Tribunal and by the church and he has decided to bring an action against a 70-year-old pensioner with no assets."

The Anglican Church had called on Betteridge to drop his claim against Mr Wurth, describing the predicament as "absurd".

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