In his homily, Father Connolly reflected upon the Gospel reading, which centered on the parable of the Prodigal Son, noting that the parable "provides context" to the Sept. 11 attacks.

"When people turn away from God and from one another, when people let fanatical ideology and corrupted creed get in the way... We turn away from life and love and turn to evil," he said.

"Evil was manifest here in Boston, Washington, D.C., New York City, and Somerset County, Pennsylvania 15 years ago on this day, and it struck our country and all of us, especially here of us in Boston who, arguably, suffered more personally than anywhere else except those in New York, in particularly terrible ways," Father Connolly continued.

He said that when faced with such a tragedy, people often question God, asking "Where is God in this? How did God let this happen?"

"For me, the answer is God doesn't let these things happen. People who abuse their free will choose to do that evil. But, where is God is a much more widely and complex answer. For on Sept. 11, 2001, God was everywhere in the midst of all that evil that was occurring," said Father Connolly.

"He certainly was there in the lives, in the hearts, and in the actions of those countless men and women in New York, Washington, and Pennsylvania who ran into those conflagrations at those various crash site and opened wide their arms to help their fellow sisters and brothers who were injured or killed, and he was there with the plane crew members, the passengers, and those who lost loved ones," he said.

After the Mass, a candlelight procession was made to the nearby Massachusetts Fallen Heroes Memorial, where Father Madden led the group in prayer.

Brian Cornell, a parishioner of the Chapel of Our Lady of Good Voyage, said the prayer service and the Mass tried to touch "the real source" of people's emotions about the Sept. 11 terrorist attack.

"It's good to remember," he said.

Elana Dekker, who helped with the music at the Mass, said the evening "was so beautiful, because it tied in together with the significance of the anniversary of 9/11 and all of our fallen heroes and that God has open arms for all of us and that he is ever present."

"It was really tied together beautifully," she said.