“The way the sex abuse scandal was handled pretty clearly shattered the trust that a lot of people had in the hierarchy,” said James O’Toole, a professor of history at Boston College, who added that the vigil had most likely also been motivated by the writings of the Second Vatican Council, in the 1960s, which expanded the role of laypeople in the church.

“It turns out that if you tell the people for 50 years that they are the church, they start to believe it and they start to act on it, and think they have the authority in a way to argue with the hierarchy,” Mr. O’Toole said.

At the time, eight other churches started vigils over their own closures, but St. Frances had the last remaining one. “This community has tested the Vatican canonical system and the U.S. legal system to their highest level,” Peter Borré, a lawyer who has supported closed churches, said to the congregation on Sunday. “Nobody else has done this.”

The archdiocese filed a lawsuit against the parishioners last year, arguing that they were trespassing. In May 2015, a State Superior Court justice ruled against the parishioners, who later appealed to the United States Supreme Court. But this month, justices refused to hear the case, and the congregants agreed to leave — after a final celebration.