Fr. Jack AhernThe man who has been asked to pioneer a new management model for three very different Catholic parishes likes to be called, simply, "Fr. Jack."

It even says so on his business card.

As he settled behind a table at Gerard's restaurant this week, Jack Ahern, 56, looked every bit the Adams Corner regular. The bearded Arlington native wore "civilian" clothes, dark-tinted glasses and —with a copy of the morning Boston Globe with his photo on the cover splayed out in front of him — a wry smile.

"A bit of overkill, don't ya think," he laughed.

Ahern's good humor and humility will no doubt serve him well when he officially begins a daunting new assignment in May. Cardinal Sean O'Malley has charged Ahern with taking charge of a newly-formed 'tri-parish' consisting of St. Peter's, Holy Family and Blessed Mother Teresa, three of Dorchester's nine remaining Catholic parishes. Taken as a whole, the tri-parish covers most of the neighborhood's northern terrain from Dorchester Bay to the Roxbury line. It's a job that longtime observers of Catholic Dorchester say requires a special person. Early reviews suggest that O'Malley made a solid pick in Ahern.

Jim Brett, a former state representative from Savin Hill who now leads the New England Council and has long been an active supporter of the parishes in this part of Dorchester, called Ahern's posting "a powerful message to this part of Dorchester."

"He's very bright and engaging, analytical and obviously someone who likes a challenge. He's coming from a secure parish in Brookline and willing to take on this first-of-its kind multi-parish duty," said Brett. "The word I hear is that he is ecstatic about the opportunity of coming here. I think Dorchester will embrace him and he will embrace Dorchester."

Ahern comes to Dorchester after 16 years at the helm of St. Mary's of the Assumption parish in Brookline, a community that has thrived under his tenure and earned him a reputation as one of the diocese's up-and-coming clergymen. He confirms that he did not seek out the tri-parish job, but could have turned down the assignment. Ahern said the offer was first extended a week ago and has not even had time to debrief with all of the local pastors in the area yet. He will spend the next few weeks getting to know the neighborhood and parishioners.

"We want to keep the three communities up and running and hopefully make them more vibrant," Ahern said. "We want to see what we can do both together and separately."

Ahern said he expects to engage lay parishioners to assist in day-to-day duties that were traditionally the preserve of priests, including ministering to the parishes' sick and elderly.

Bill Walczak, a parishioner at Blessed Mother Teresa, says that the announcement of Ahern's appointment — made at Masses on Sunday— was greeted with mixed emotions.

"There are people who are fearful about what it means to share a pastor with two other churches," Walczak said. "It seems to be a lot of work for one person to manage one parish, let alone three. I think the general feeling is 'We'll have to make the best of it.'"

"Obviously we're in a new era of Catholicism in Boston. We're searching for a new way to practice our Catholicism and it's something that we're all trying to figure out," said Walczak. "There've been people saying let's do a survey of the community and what kind of things we should be doing."

Whereas individual pastors sometimes wielded strict controls over even minor details of individual parishes, Walczak said he expects that lay leaders will likely exercise more authority under the cluster model. The Archdiocese of Boston's Office of Cultural Diversity led a series of meetings with parishioners from the three churches beginning last January. Notes from those meetings indicate that a common concern was the need for a new pastor to "distinguish between common needs that all parishes share and the individual needs of the ethnic communities and strike a balance between the two."

Brett, who along with his wife Patti have served as informal advisors to several Dorchester pastors over the years, has the sense that the tri-parish effort is going to be a special project of the Archdiocese in coming months.

"I'm getting the impression from the Archdiocese that this is going to be a high priority to make this a success," Brett said. "It's not going to not be just [Ahern]. There'll be others to make this cluster a success."

As of this week, Ahern has not decided where he will live. Two logical choices, he said, would be Holy Family parish, which has a residence for priests on Lingard Street, or St. Amrbose in Fields Corner.

John J. Fahey, a parishioner at St. Peter's on Bowdoin Street, said that the tri-parish concept is a positive step if it ensures the salvation of each individual church.

"If that's what it takes, I'm all for it, if this means that each parish can maintain its own identity and buildings," said Fahey. "St Peter, in addition to [having]such an architecturally significant building, has a large Cape Verdean community with such a strong presence in Bowdoin-Geneva. All three parishes have distinct gifts to offer and it's so important that they stay intact."