By Mark Abrams

PHILADELPHIA (CBS) — The resignation of Pope Benedict XVI caught many Vatican watchers by surprise.

Philadelphia-based Catholic journalist Rocco Palmo writes about the Vatican and church politics and says it was a stunning and historic announcement (read related story).

Palmo says Pope Benedict is making a strong statement about the role of the papacy and those who fill it in the future.

“He’s really moving the papacy into a new age where, you know, it used to be the popes who would get sick, they could be confined for a year or two. They wouldn’t have the public part of the role that modern popes have,” he says. “And, so this is Benedict’s way of saying, ‘Look, you need to be out there. The pope needs to be public. If he can’t travel, if he can’t appear, if he’s weak, he can’t effectively govern, he can’t effectively do his job.’”

Palmo says it now triggers a conclave to elect Pope Benedict’s successor sometime next month.

He says Archbishop Charles Chaput, the leader of the Philadelphia area’s Roman Catholics, will not be able to participate because he has not yet been elevated to the post of cardinal.

“However, there will be a Philadelphia vote in the conclave,” Palmo says. “As Cardinal Rigali, the retired archbishop, still maintains his right to elect the new pope. So, Cardinal Rigali will be in the conclave.”

Rigali retired to the Diocese of Knoxville, Tennessee after leaving his post in Philadelphia.

Listen to KYW Newsradio’s Harry Donahue discuss the Pope’s resignation with Vatican observer Rocco Palmo: