Primate of All Ireland and Archbishop of Armagh Cardinal Seán Brady has apologised for the failure of the Church to respond adequately to the victims of clerical child sexual abuse.
At mass in the RDS during the International Eucharistic Congress, Dr Brady said he wanted to apologise for "the times when some of us were blind to your fear, deaf to your cries and silent in response to your pain".
He said the victims were "little ones who were frightened, alone and in pain because someone was abusing them".
Dr Brady described the healing stone, which was placed in the arena on Sunday, as a reminder of "those children and young people who were hurt by a Church that first betrayed their trust and then failed to adequately respond to their pain".
He said what the stone represents is a stark warning that there can be no passing by on the other side and "no room for half-heartedness in our care for the vulnerable and the young".
Dr Brady prayed that one day the stone, which is inscribed with a survivor's prayer, might become a symbol of conversion, healing and hope and of a Church that has learned from the mistakes of the past.
He said the Church lamented the burdens of the painful memories carried by the survivors of abuse and prayed for healing and peace for those whose suffering continues.
Meanwhile, an organisation representing survivors of child abuse in the Catholic Church has criticised the organisers of the International Eucharist Congress for failing to consult victims' representative bodies before deciding to exclude them from the global event in Dublin.
Michael O'Brien of the Right to Peace organisation criticised the Secretary General of the Congress, Fr Kevin Doran, for saying survivors' groups were not invited to the gathering on the advice of people caring for victims and of some individual survivors.
Earlier today Fr Doran told journalists at the RDS there was a concern that bringing in groups would be seen as part of a public relations process.
He decided instead that any survivor who emailed him was provided with a pass to the Congress.
But Mr O'Brien told RTÉ News the Congress organisers should have contacted the representative organisations to ensure that all survivors got to know about the gathering.
He said those who wanted to go would have done so respectfully.