Catholics in the Archdiocese of Philadelphia have planned their first "Mass Mob" in the north of the city, seeking to rally scores of people to a beautiful but sparsely attended church.

"It's an opportunity for people from all over the archdiocese to come together as a community," Mass Mob Philly organizer Ben DiFrancesco, a 28-year-old software engineer, told CNA March 14.

"It's an opportunity for people to enjoy these big, beautiful, old church buildings that they maybe normally don't get to see at their regular parish."

DiFrancesco is one of the organizers who are using social media to encourage as many people as possible to attend Mass at St. Francis Xavier, The Oratory, in Philadelphia's Fairmount neighborhood on the morning of March 23. They are asking attendees to arrive at 11:15 a.m., 15 minutes before the Sunday Mass begins.

DiFrancesco said he was inspired by news reports of a similar endeavor in Buffalo, N.Y.

"It really struck me as a great idea that could work equally as well in the Archdiocese of Philadelphia," he said. "Call it a movement of the spirit or whatever, but I talked it over with people and they gave me encouragement to give it a shot."

Several dozen people have responded to the idea. As of the afternoon of March 14, over 50 people had RSVP'd at the Mass Mob Philly Facebook event page.

St. Francis Xavier is DiFrancesco's home parish. The church building was built in 1898.

"It's just a beautiful building in a wonderful neighborhood," he said, praising its three large rose-shaped stained glass windows, its high columns and arches, and its artwork.

He said the church is like many city churches in Philadelphia and around the U.S. where shifting demographics mean "the building really doesn't match the size of the congregation anymore."

"It was built in a time when the neighborhood was pretty much all Irish immigrants. It had a huge Catholic population," he said. "It was built to serve that kind of congregation."

"There's plenty of space when you go to Mass in a beautiful building. It's a good opportunity for people to come together and enjoy that."

DiFrancesco said that the Mass Mob is intended to support the local parish community and boost "parish morale" by filling the pews again. It could also boost donations to the collection plate.

The church is served by priests with the Congregation of the Oratory of St. Philip Neri, commonly known as the Oratorians. The priests were "enthusiastic and willing" to help consider the logistics of the event.

He also had special words for anyone considering starting a Mass Mob in their own diocese.

"The first thing I would say is 'go for it!' Don't hesitate," he said. "Have a clear understanding of what you're trying to achieve."

"Just put together the online and social media assets and just start getting the word out," he said.

Social media have played a role in both the Buffalo and the Philadelphia Mass Mobs. DiFrancesco said the Mass events can help counter the "general sense" that social media in modern life "water down or dilute our authentic friendships or relationships with people."

"This is one of many ways that we Catholics can use these things as tools not to replace authentic face-to-face relationships, but to bring people together in reality, in community," he said. "I think that we can demonstrate that in a way that the world needs to hear."

DiFrancesco suggested new Mass Mob organizers contact him or the organizers of the Buffalo event, who had advised him on launching his own effort.

The Philadelphia organizers work with the parish staff to ensure they can accommodate a larger than usual congregation. They plan to select other churches for future Mass Mobs by means of public votes on social media.

"There are plenty of beautiful churches in Philly that we could use," DiFrancesco said. "I think that as we move forward, the goals will evolve and we'll get a clearer sense of what people are getting out of it."

The Mass Mob Philly website is www.massmobphilly.org.