A British survivor of child sexual abuse who set up a charity to help other victims has been appointed by Pope Francis to his new commission to protect children and help people who have been abused.

Peter Saunders, 57, was telephoned by Cardinal Seán O’Malley and asked if he would consider joining the commission, which will report directly to Pope Francis. Saunders – who was abused as a child for more than five years by two priests, a teacher and a member of his family – said he agreed immediately. The invitation came six months after Saunders had a private meeting with the pope, which he said involved a no-limits discussion.

“I have been a thorn in the side of the Catholic church for some years. When I was called to see if I would be prepared to meet the pope it didn’t take me very long to say yes,” said Saunders.

“When I met him in July and started conversing with him, I told him the church needed to get its act together, that it needed to support survivors and to do more to protect children. I said to the pope I would be coming back to see him, but I never dreamed I would be invited back to join his commission.”

The Vatican released the names of the final nine members of the commission on Wednesday. It is expected to hold its first full meeting at the Vatican in February. The commission has been set up to support survivors of abuse and to protect children from future abuse.

Saunders said he was flying out to Rome for the commission’s inaugural meeting. He said he intended to use his role to make sure there was a change in the way the church behaved towards victims in future.

“I am going to raise issues around the coverups of the past, and also to say that victims organisations need some serious funding. I want to try and help change the church for the better.”

Saunders set up the British-based National Association for People Abused in Childhood (Napac) in 1995 after realising there were millions of adults who – like him – were experiencing the psychologically painful effects of abuse inflicted on them as children.

The charity provides direct support for those who have been abused.

Saunders said he had no problem with joining the commission and working with the Catholic church even though his abusers had included Catholic priests. He has in the past said he remained afraid of the clergy.

“I was brought up as a Catholic and have never lost my faith,” he said. “My faith has always sustained me, but it is about my relationship with God rather than going through a third person. This role provides me with an opportunity to have a kind of influence for good on the church and I am going to go for it, I am not afraid of it.

“If I can help the church to help people to move on with their lives, if I can help build bridges with victims – the church has got an appalling reputation on this – but if I can help change this, then I will be doing something positive.”

Saunders said Pope Francis had done more for him than anyone else because he listened to him.

“He granted me something that the prime minister, and the deputy prime minister and all these other ministers of state in the UK never have. I had the benefit of a discussion with him, with no limits … It was a life-changing moment for me,” he said.

Saunders said he was optimistic about the commission because it reported directly to Pope Francis.

“He is trying to carry out a great deal of reform and there will be resistance to that, which is why there is no intermediary between the pope and the commission members.”

Although he is still undergoing therapy for the abuse he suffered as a child, Saunders said he had been able to move on with his life, while many others have not.

“My children have grown up and we have grandchildren on the way, so in a way, although I am still having therapy for the stuff that happened 50 years ago, I have sort of moved on, but millions have not been able to and if I can help them to by doing this work, that will be something very positive.”