Cardinal Sean O'Malley is leading a novena of masses leading up to Pentecost to pray for forgiveness and healing for the sexual abuse by clergy in the Archdiocese of Boston.

The archdiocese has called the nine days of prayer "a pilgrimage of repentance and hope." It is the first time that a series of masses has been offered for this intention since the scandal broke in 2002.

The first mass was celebrated at the Cathedral of the Holy Cross on Ascension Thursday. Cardinal O'Malley and about 25 priests prostrated themselves on the sanctuary for nearly 10 minutes as 30 intentions were read, asking for forgiveness for the "sins of your priests" and "harm brought to your Church."

"We are sorry that this pain was hidden and the sins were not exposed," Cardinal O’Malley said in his homily. "So much suffering was caused by the actions and inactions of bishops and priests."

"We come together in this pilgrimage overwhelmed by the sadness and pain sexual abuse has caused our Church,” he reportedly said. "The sexual abuse of children is, for us, the wounds on the body of Christ.”

The other masses are being held at parishes that were served by priests accused of or convicted of sexual abuse. A victim of the abuse, or a victim’s relative, is to address the assembly at each mass. A crucifix from a parish that was closed after the abuse scandal is on display at each mass.  About on fifth of the Archdiocese’s parishes have been closed or are slated to be closed since the scandals erupted.

Barbara Thorp, director of the archdiocese's Office of Healing and Assistance Ministry, said the masses aren’t just “a pious exercise” but the people of God coming together to sincerely and humbly beg for God's help.

The archdiocese has paid more than $100 million in settlements for hundreds of sexual abuse claims. Through its office of Pastoral Support and Outreach, it continues to offer counseling to victims, train adults to recognize signs of sexual abuse, and teach children how to prevent abuse and work closely with civil authorities to prosecute and prevent abuse.