It’s a telling detail: when the abused come to the witness box of the royal commission, they affirm. They were born deep inside the church to families that never missed mass and sent their kids to the parish primary school over the road. But they don’t swear on the Bible when they come to give their testimony.

Chrissie Foster affirmed. She was the first witness on the first day of the first Melbourne sitting of the Royal Commission into Institutional Responses to Child Sexual Abuse. She deserved her place at the top of the billing.

Two of her children were raped by Father Kevin O’Donnell, not in the dark ages but in suburban Melbourne in the 1990s. One is dead, the other is permanently incapacitated. The church, though it had known about O’Donnell’s criminal ways for at least 30 years, tried to fob off Chrissie and her husband Anthony with pastoral rhetoric and a few dollars.

It’s hard to imagine this commission ever having been called but for the Fosters’ implacable and dignified pursuit of the church. They never lost their tempers. Their good humour has somehow survived. Their judgment has seemed impeccable at every turn.

Twelve years ago, when their campaign began, they went shyly on television in disguise. But the resistance of the church compelled them to put their names and faces to the story of their daughters’ abuse and their own mistreatment. They have told it so many times but what they always wanted was a royal commission and now they stood side by side in the witness box to tell their story all over again.

The room was crowded and the sound system appalling. Up the back we often strained to hear as they took turns to read from Chrissie’s 112-paragraph statement. They were at it for the best part of an hour, steady and quiet all the way. This might be the last time they have to go through this ordeal.

It’s a story that still shocks long after it’s ceased to surprise. When they were done, none of the barristers representing the bishops and QCs whom they’d taken apart in their statement had a question to ask. Nothing the Fosters said was challenged.

They left the box hand in hand. There was applause and one or two in the crowd gave them a standing ovation. The Fosters did nothing to encourage this. There wasn’t a trace of triumph about them.