Hillsong founder Brian Houston says it is quite likely his father sexually abused multiple children and the true number of victims may never be known.
Frank Houston confessed to his son about one case of abuse in 1999, which occurred several decades earlier.
After it came to light, Frank Houston was banned from preaching but nothing was done to inform the public or alert authorities.
Houston is standing trial for allegedly covering up the abuse until his father's death in 2004 and has pleaded not guilty.
"I have no doubt now my father was a serial pedophile and we'll probably never know the extent of it," Houston told Sydney's Downing Centre Local Court on Monday.
Magistrate Gareth Christofi asked Houston if he had any concerns his father would sexually abuse other children after he failed to report the allegations.
"Did you not think, 'people really ought to know about this ... because it's potentially dangerous'?" Mr Christofi asked.
"At 78 years of age, failing health, I didn't believe he still was a risk to anyone," Houston replied.
Houston also claimed there was no evidence his father continued to abuse minors after the late 1970s.
With the benefit of hindsight, Houston said he now believed the church could have taken a better course of action.
Houston described himself as "more educated" than two decades ago, before widespread sexual abuse in religious circles became common knowledge.
"Church people are a whole lot more aware ... than they were," he said.
The court also heard Houston didn't believe his mother ever understood the gravity of his father's crimes because she was from a "different generation".
"She was complaining about Frank being treated too harshly," Houston said.
"I said, 'Mum it's not just immoral, it's criminal' but I don't think she ever got the difference."
Houston told the court his father met his victim at Sydney's Redfern station and organised to pay him $2000, later topped up with $10,000 which Houston had a role in facilitating.
"It was his feeble attempt to try and right the wrong," Houston said.
Houston also said he spoke to his father's victim by phone and offered him counselling on behalf of the Assemblies of God in Australia.
"He said 'I don't want your bloody counselling' and he cut the meeting short," Houston said.
Houston said he was involved in organising to pay the victim the additional money which he did through a lawyer to avoid it appearing like a cover-up.
He said he wanted to make sure he was not in any way silencing the victim or preventing him going to the police in the future.
"I was wanting to be careful that there was no cover-up here ... and it couldn't be seen that there was a cover-up," Houston said.
It was his intention to distance himself and the church from the payment, he said.
"I wanted to be sure whatever document was being drawn up that this was a payment from Frank to (the victim) - between those too.
"I was trying to stay arms length from it."
Houston said he later received a call from the victim saying he had not been paid and had been told by Frank Houston he had no money.
"I was frustrated no money had been paid but also I was frustrated Frank had told the victim to phone me," Houston said.
Houston said it was his understanding the $10,000 was eventually paid but he did not know by whom.
"Do you know what the terms for the payment ended up being?" Houston's lawyer Phillip Boulten SC asked.
"No," he replied.
The hearing continues.
