A senior US churchman visiting Dublin to examine how children are protected against paedophile priests has told parishioners he had not come to offer a quick fix.
Cardinal Sean O'Malley, the Archbishop of Boston, called on survivors who were harmed, as well as lay people and the religious, to come forward.
The cleric said the crisis of the sexual abuse of minors had profound repercussions for entire communities.
"I come to listen, not to offer a quick fix," Cardinal O'Malley told Mass-goers in St Mary's Pro Cathedral in Dublin.
"I come to listen to your pain, your anger, but also your hopes and aspirations."
Dublin Archbishop Diarmuid Martin celebrated Mass with the Cardinal at the start of his investigation visit.
The unprecedented probe was announced by the Pope in his letter to the Catholics of Ireland last March in response to the catalogue of abuse outlines in the Murphy and Ryan reports.
The Cardinal said much had already been done in Dublin to address the crimes of the past, to ensure the safety of children and to provide assistance to victims.
"The task of the visitation is to bring new eyes to the situation, to verify the effectiveness of the present processes used in responding to cases of abuse," he added.
"We are not here to reduplicate investigations or studies of the past."