By Pat Loeb

PHILADELPHIA (CBS) — In the scant history of papal resignations, this is the first one attributed to age and loss of vigor. KYW Newsradio spoke to a local historian about precedents for Pope Benedict XVI stepping down (read related story).

Popes have gotten older than 85, popes have gotten gravely ill, Pope John Paul II was critically wounded by a gunman, but they stayed Pope. The only two verifiable resignations in church history were Celestine V, a hermit, immediately overwhelmed by the office and Gregory XII, who resigned to save a splintering church 600 years ago. Still, St. Joseph’s history professor Alison Williams Lewin says the tradition of toughing it out may not be the most responsible course.

“I would hope someone in the position who felt no longer able to discharge his duties would think of the great good of the church,” she says, “and would do as Benedict has done.”

Lewin says it’s not clear whether this will open the door for future popes to feel more comfortable taking that step, and whether it is ethically correct.

“That is a conversation he will have to have with his higher authorities,” she says.