Feb. 12, 2013— -- When most people retire, they think of going to Florida, playing Bingo or filling their spare time with favorite hobbies.
When U.S. presidents leave office, they do charity work and oversee the building of their presidential libraries.
FULL COVERAGE: Pope Benedict XVI Resignation
For Pope Benedict XVI, the first pope to resign in 600 years, there is no precedent as to how he'll spend his retirement - or even what title he'll have.
"We're in rather new territory so we're going to have to see if they bestow him a title or if he even has one," said Matthew Bunson, general editor of the Catholic Almanac and author of "We Have a Pope! Benedict XVI."
What we do know is this:
The pope, who gave slightly more than the standard two weeks' notice for quitting a job, will retreat to Castel Gandolfo, the swank papal vacation residence, after his last day as pontiff on Feb. 28, according to a Vatican spokesman.
His primary residence, according to the spokesman, will be a monastery within Vatican territory.
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The rest is anyone's guess, said Christopher Bellitto, a professor at Kean University in New Jersey who has written nine books on the history of the church.
"I would be very surprised if he didn't make frequent and indulgent visits to a nice villa in Bavaria," Bellitto said of the German-born pontiff.
Pope Benedict XVI, born Joseph Ratzinger, made it no secret that he never aspired to be pope, and was instead following the plan of God.
Bellitto said the pope, who is 85, will likely spend the final chapter of his life out of the public eye, "living the quiet life of retirement he probably thought would happen after the papacy of John Paul II."
"He'll probably be living with his brother, [Monsignor Georg Ratzinger, 89]. They are very close," Bellitto said.
It's likely the pontiff will keep a small private staff to help him with matters as he adjusts to life out of the public sphere, Bunson said.
"Whether his current secretary remains in his post we'll have to see," he said.
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Not much is known about the pope's health.
In his resignation statement, the pontiff said his physical strength has deteriorated in the past few months due to "an advanced age."
He also mentioned the "strength of mind and body" necessary to lead the 1 billion Catholics worldwide.
If he is able to, Bellitto said he believes the pope will keep writing, perhaps on the Holy Trinity, a topic of great interest to him.
Bunson and Bellitto both agree that on Feb. 28 at 8 p.m. Central European Time, the moment Pope Benedict XVI will step down, he'll choose to live a very private life, partly out of respect for his successor.
"This strikes me as an incredibly noble and humble action," Bellitto said. "And when walks away from it, he really wants to walk away from it."