Within a decade, the Franciscan priest had left his New Hampshire home to feed and serve the poor in that same Kensington community, now more known for its role in Philadelphia's opioid crisis.
Today, his order's soup kitchen – the elegantly named St. Francis Inn – is a neighborhood institution, and so is Duffy, 78. In the last 31 years, he has had a unique vantage point on a community that is at once long-time home for proud residents, notorious opioid epicenter, and, in pockets, gentrifying hot spot.
Duffy, known to all as "Father Mike," was sent here by his Franciscan superiors in 1987 and never left. His St. Francis Inn service record is beat only by Sister Mary Augustini, who arrived one week earlier than Duffy and won't let him forget it.
Duffy is tall and lean, and has a mean sweet tooth he can't resist indulging when the weekly donation arrives from Stock's bakery in Port Richmond.
He calls his guests "food insecure," but tries to serve them in ways that go beyond basic nutrition.
Duffy or another resident priest starts each day with Mass at 8:30 a.m. – one of the few times they wear their traditional brown habits. Then a team of nine full-time staffers and three year-long volunteers sort through donations and prepare the day's main meal (usually a sandwich or piece of bread, a hot entree such as stew, salad, and a dessert). Three days a week, they also serve a breakfast of doughnuts or cereal with hot coffee or tea.
Duffy and the staff, most of whom have been at the inn for more than 20 years, usually share the same food for their own dinner. They work five days a week, taking one day off and using the seventh for prayer.
Staying centered on prayer – along with sharing laughs where they can – is essential to avoiding burnout in a community where everyone knows that the person who is served dinner one day may be dead of an overdose the next.
"You can't take yourself too seriously," Duffy said. "You just do the best you can and learn to be satisfied with that."
The St. Francis Inn welcomes everyone, regardless of whether they are sober. Scores of volunteers wait on tables, serving restaurant-style rather than making people line up for food, because the staff thinks that is a more dignified way to dine. It's challenging, too, as they regularly serve 300 guests in an hour and a half.
One of those volunteers, Bill Long, used to be a guest. He moved to Kensington in 1974 after the death of his wife and two daughters, and drowned his misery in methamphetamines and alcohol for 15 years. In recovery, he found the St. Francis Inn.
"I get along with all the people out there," said Long, 71. "They know me from around the neighborhood, and they know I don't take no crap."
Duffy said that when he arrived in Kensington in the late 1980s, the most common drugs of choice were crack cocaine and Tywall, a substance inhaled through the nose to produce a quick high.
Cocaine "was an upper, so everyone was agitated, so we'd routinely have two or three fights in the yard during the meal," Duffy said.
Carmelo Gonzalez, 66, has been eating at the St. Francis Inn since the '80s and has also witnessed the changes in the guests because of changing drugs.
"Back in the old days, it was a little more violent than it is now," Gonzalez said.
Heroin has changed everything.
"Now, sometimes you come down Kensington through Allegheny, it looks like a set for a zombie movie," Duffy said. "They're all strung out on drugs, leaning against the lampposts, flopped in the doorway, in the gutter."
When he first moved to the neighborhood, the batteries would be stolen out of his and others' cars on the street "routinely, once every two weeks," Duffy said.
Around four years ago, Duffy was awoken by one of the guests of the soup kitchen who told him that someone had stolen the TV out of the nuns' house.
"I got in the car, chased [the robber], and I got the TV back after a physical struggle," Duffy said. "I said, 'Do you know what you're doing? You're stealing a TV from nuns.'"
"They're away from the problem, but they're not solving the base problem of the addiction," Duffy said. "They cleared the tracks, people moved into the tunnel. They cleared the tunnel, people are going to be moving into the neighborhood."
Since January, Duffy has seen a dip in the number of diners – around 10 percent. Whether the decrease is related to nearby gentrification, the soaring overdose rates, or something else, Duffy doesn't know.
He does know that the house across from St. Francis Inn where he has lived for 31 years was once valued as low as $1,500. Now, the house is worth $80,000.
"We get, about every other morning, a little slip of paper in the door, 'Do you want to sell this house?'" Duffy said.
Duffy faces the future knowing that the Franciscans' mission will always be needed somewhere.
"If we don't get any business, there's no purpose for us to be" in Kensington, Duffy said. "Wherever the poor go, we'll move there."
Despite the trials of the neighborhood, he hasn't thought about asking for a transfer.