ROCHESTER, N.H. -- Slain U.S. journalist James Foley was living his faith by bringing images to the world of people suffering from war and oppressive regimes, a Roman Catholic bishop said Sunday at a Mass in his honour.

Bishop Peter Libasci said even after Foley was captured for the first time in Libya in 2011, he "went back again that we might open our eyes."

The Mass was attended by Foley's parents, John and Diane Foley, and hundreds of others in their hometown of Rochester, New Hampshire. Afterward, Libasci read aloud a letter from the Vatican extending the condolences of Pope Francis.

"Thank you for loving Jim," Diane Foley told the crowd after the Massachusetts.

The crowd filled every pew and people stood three deep at the back of the church and along both sides of it. Gov. Maggie Hassan, along with U.S. Sens. Jeanne Shaheen and Kelly Ayotte, attended the memorial.

Foley was kidnapped on Thanksgiving Day 2012 while covering the Syrian uprising. The Islamic State group posted a Web video Tuesday showing his killing and said it was in retaliation for U.S. airstrikes in northern Iraq.

In a packed Our Lady of the Holy Rosary church, the bishop frequently addressed Foley's parents and stressed their son's connection to family. He also prayed for another captive journalist, Steven Sotloff, and all captives.

"Jim went back again that we might open our eyes," Libasci said. "That we might indeed know how precious is this gift. May almighty God grant peace to James and to all our fragile world."

Libasci said after the Mass that people shouldn't think of vengeance.

"Look at what it's done already," he said. "Look at the heartbreak."

A funeral for Foley will be Oct. 18, what would have been his 41st birthday.

Also Sunday, the U.S. government said Peter Theo Curtis, a journalist who was held hostage for about two years by an al Qaeda-linked group in Syria, was released. White House national security adviser Susan Rice said Curtis, who wrote under the byline Theo Padnos, is now safe outside of Syria.

Speakers praised Foley's determination to report on the Syrian people uprooted by conflict.

"Tonight we want to honour freedom and love: the freedom that James so vehemently believed that all people deserved," said Nadia Alawa, founder of NuDay Syria, a Massachusetts-based organization working to ease the pain and loss in Syria.

The world's largest bloc of Islamic nations denounced Foley's "heinous" killing and reiterated its support for international efforts to confront the Islamic State fighters.

Iyad Madani, chief of the Organization of Islamic Cooperation, said in a statement Saturday that the actions of the Islamic State group have nothing to do with the values of Islam or his organization's founding principles of tolerance and co-existence.