The head of the popular Hillsong Church, Brian Houston, has sought to distance his organisation from the actions of his father, Frank Houston, whose alleged sexual abuse of up to nine children is under examination at the royal commission into institutional responses to child sexual abuse.

Pentecostal preacher Frank Houston, who died in 2004, confessed in 2000 to sexually abusing a boy in New Zealand more than 30 years earlier. He was immediately sacked by his son, Brian Houston, who was then national president of the Assemblies of God, a worldwide grouping of Pentecostal churches.

In a statement outside the royal commission on Wednesday morning, Brian Houston commended the hearing for making church leaders “uncomfortable” because “we have a collective responsibility to protect children”.

“We must be diligent and never let our guard down,” he said.

However, he said people should understand that the abuse claims being examined happened before Hillsong existed, “when I was a teenager myself”.

The royal commission is examining the responses by the Sydney Christian Life Centre and Hills Christian Life Centre (now Hillsong Church) and the Assemblies of God in Australia (now Australian Christian Churches) to allegations against Frank Houston.

It was revealed on Tuesday that Frank Houston had allegedly abused up to nine boys in Australia and New Zealand, and that no allegations were referred to police or civil proceedings commenced in Australia. An investigation by executives of the Assemblies of God revealed at least 50 New Zealand pastors were aware of the abuse.

In 1977 Frank Houston established the Sydney Christian Life Centre. His son Brian and daughter-in-law Bobbie joined the ministry in 1978, and in 1983 founded the Hills Christian Life Centre. In 1999 the two centres merged, and were renamed Hillsong Church two years later.

In his statement, Brian Houston reiterated his denial of accusations levelled at him on Tuesday by Frank Houston’s victim, referred to as AHA, who said that in a phone conversation Brian Houston had told him: “You know it’s your fault all of this happened – you tempted my father.”

On Tuesday the royal commission heard AHA had told his mother in 1978, who advised him against harming the church. Nothing was said until 20 years later when his mother told pastor Barbara Taylor of the Emmanuel Christian Family Church.

It sparked an investigation by the Assemblies of God, and Frank Houston was stood down from preaching for 12 months, later extended indefinitely when further allegations came to light, but no police referral was made.

Tuesday’s hearing also heard that in 2000 AHA met Frank Houston and a third unknown man at Thornleigh McDonald’s, where Frank Houston allegedly told him “I want your forgiveness for this” and offered him $10,000. The unnamed man then placed a food-stained napkin in front of him and told him to sign it for the money, AHA told the commission.

Among the aspects of the case being examined is the nature of Brian Houston’s role in the responses to AHA’s allegations.

Under questioning from the legal representative for Hillsong Church and Brian Houston, Mark Higgins, AHA said he was relieved to then learn Frank Houston had admitted to the abuse, but didn’t want the matter investigated.

Higgins also pursued a lengthy line of questioning on the timing of phone calls, and exactly when AHA went through puberty – the time at which AHA had earlier testified Frank Houston stopped abusing him.

Higgins suggested the abuse stopped before the Sydney Christian Life Centre became Hillsong Church.

Higgins did not ask any questions regarding AHA’s accusation that Brian Houston blamed AHA for “tempting” his father, despite Brian Houston denying it in a statement outside the royal commission just hours before.

The hearing continues on Wednesday with witnesses from Hillsong Church, the Assemblies of God, and Australian Christian Churches, including Taylor and Brian Houston.