(CNN) -- Pope Francis met Monday with six victims of sexual abuse by clergy members, acknowledging that the failure of church leaders to act led to greater suffering.
"Before God and his people I express my sorrow for the sins and grave crimes of clerical sexual abuse committed against you. And I humbly ask forgiveness," Francis said in a homily during Mass with the victims, according to a text of the statement provided by the Vatican.
"I beg your forgiveness, too, for the sins of omission on the part of Church leaders who did not respond adequately to reports of abuse made by family members, as well as by abuse victims themselves," he said. "This led to even greater suffering on the part of those who were abused and it endangered other minors who were at risk."
He said "sins of clerical sexual abuse against minors have a toxic effect on faith and hope in God."
The six sex abuse victims -- three men and three women from Britain, Ireland and Germany -- each met privately with Francis for about 30 minutes, Vatican spokesman Rev. Federico Lombardi told reporters.
The meeting Monday took place at the Pope's private residence, a Vatican guesthouse called the Casa Santa Marta. It was Francis' first meeting with sex abuse victims since becoming pope.
Lombardi said they emerged moved by what he described as a "profound spiritual encounter and dialogue."
Despite complaints from groups critical of the church's handling of sex abuse scandals that the meeting was little more than a stunt, Lombardi said it was "absolutely clear it was not a public relations event."
Francis became Pope in March 2013. While critics have said he should have met with victims earlier, Francis has said he believes the Church has been unfairly attacked.
Cardinal Sean O'Malley, the archbishop of Boston, was asked by the Pope to help organize the meeting, the cardinal's spokesman said.
O'Malley is a member of a new commission spearheaded by Francis -- the Commission for the Protection of Minors -- to advise him on ways to help move forward after the Church's sex abuse crisis.
One member of the group is a woman who was a sex abuse victim.