SOUTH BOSTON -- Shortly after Dorchester native and Marine Cpl. Paul Garrity landed in Da Nang in 1969 at the age of 20, his gunnery sergeant asked their guide if any snakes lived in Vietnam.

"Yes," the guide replied. "Ninety-eight percent of them are poisonous. The other 2 percent will eat you."

Garrity, now 74, remembers spending weeks at a time in the jungles of North Vietnam, sleeping under his poncho and keeping an eye out for snakes. He received two Purple Hearts for his service from 1969 to 1970. One was for wounds received during a mortar attack, which left him with several broken bones. The second was for rocket fire that left fragments of shrapnel lodged beneath his skin. The pain was difficult for him to describe.

"Your mind, it doesn't go blank but... I can't explain it," he recalled.

While he was in Vietnam, his mother went to church every day to pray novenas for him. Garrity credits those novenas with bringing him home, even as so many of his friends lost their lives.

"If I really dug down deep," he said, "I knew I'd be okay because of my mother's protection. The faith was very healing. There's no question about that."

Wearing one of his Purple Hearts, Garrity and dozens of other veterans, service members, local officials, and their families crowded St. Brigid Church in Boston on Sept. 10 for its 42nd annual Vietnam Memorial Mass.

"May their souls rest in peace," said Marine Corps League National Commandant Warren Griffin. "And may their families have peace. We can't live in hatred."

Griffin, now 73, served as a naval gunfire observer in Vietnam from 1969 to 1970, and attends Mass daily.

"It's just so nice to see the respect that's given to the Vietnam veterans," he said. "When we came home, there was so much disrespect. And it's events like this that keep the respect going."

In his homily, Father Robert Casey quoted the Gospel of John: "No one has greater love than this, to lay down one's life for one's friends."

"Most of us will never be asked to love our neighbor by laying down our lives," Father Casey said. "But today we can honor (veterans') lives by at least trying to love our neighbor, and our enemy, a little better than we have."

Boston Mayor Michelle Wu, City Council President Ed Flynn, and former Vatican Ambassador and Boston Mayor Ray Flynn were among those who attended the Mass.

Ed Flynn's uncle Dennis B. Flynn, who died in 2008 at age 67, was a sergeant in the U.S. Army during the Vietnam War.

"Dennis was almost like a second father to me," Ed Flynn told The Pilot. "Someone I loved and respected. He lived his life by example and was committed to his faith and committed to his neighbors."

Ed's father, Ray Flynn, remembered Dennis as a loyal and caring younger brother.

Both as an American and as a Catholic, Ray Flynn said, Dennis "always fought for justice and other people."

"He was very sad about the people that were left behind," Ray Flynn added. "Many of them were longtime friends from South Boston."

During his time as a high school basketball coach, Ray Flynn saw many of his students go to Vietnam and not come back. So, the annual Mass means "all the world" to him.

"It's an opportunity to see the families of the deceased be given all the respect and honor that they deserve," he said.

Mary Lou Rosher and her husband Thomas prayed for their 18-year-old grandson Andrew, who was leaving his home parish that night to serve in the Marine Corps. The Roshers have several friends and relatives who served in Vietnam.

"They weren't treated very nice when they came home," said Andrew's great aunt Margaret Rosher.

Margaret's son, Petty Officer Third Class Jacob Orchard, committed suicide in 2005 while serving in the U.S. Navy in San Diego. He was 23. Margaret wears his dog tag around her neck, along with one of the bullets fired during his 21-gun salute.

"It keeps them in your heart and soul," she said of the Mass. "They're with us constantly."

"War is hard," Mary added. "And freedom costs."

After Mass, parishioners gathered at Medal of Honor Park across the street to rededicate South Boston's 42-year-old Vietnam War memorial, one of the first built in the country. It is a slab of black granite carved with 25 names of South Boston residents killed during the war, and a challenge to those who survived them: "If you forget my death, then I died in vain."

Father Casey delivered the invocation.

"We remember all those men and women who lost their lives safeguarding our freedoms around the world," he said. "We pledge never to forget and do all in our power to promote peace throughout the world."