VATICAN CITY — With a few words in Latin, Pope Benedict XVI did what no pope has done in more than half a millennium, stunning the world by announcing his resignation Monday and leaving the already troubled Catholic Church to replace the leader of its 1 billion followers by Easter.
Not even his closest associates had advance word of the news, a bombshell that he dropped during a routine morning meeting of Vatican cardinals. With no clear favorites to succeed him, another surprise likely awaits when the cardinals elect Benedict's successor next month.
"Without doubt this is a historic moment," said Cardinal Christoph Schoenborn, a protege and former theology student of Benedict's who is considered a papal contender. "Right now, 1.2 billion Catholics the world over are holding their breath."
The move allows for a fast-track conclave to elect a new pope, because the traditional nine days of mourning that would follow a pope's death don't have to be observed. Though the 85-year-old Benedict will not himself vote, he has hand-picked the bulk of the College of Cardinals — the princes of the church who will elect his successor — to guarantee his conservative legacy and ensure an orthodox future for the church.
Benedict said as recently as 2010 that a pontiff should resign if he got too old or infirm to do the job, but it was a tremendous surprise when he said in Latin that his "strength of mind and body" had diminished and that he couldn't carry on. He said he would resign effective 8 p.m. local time on Feb. 28.
Bishop Robert Lynch, who leads the Diocese of St. Petersburg, visited the Vatican last May and met with the pope. On Monday Lynch said, "I sensed when we briefly reminisced about our work together . . . that I was saying good-bye.''
As a top aide, Benedict watched from up close as Pope John Paul II suffered publicly from the Parkinson's disease that enfeebled him in the final years of his papacy. Clearly, Benedict wanted to avoid the same fate as his advancing age took its toll, though the Vatican insisted the announcement was not prompted by any specific malady.
The Vatican said Benedict would live in a congregation for cloistered nuns inside the Vatican, although he will be free to go in and out. Much of this is unchartered territory. The Vatican's chief spokesman, the Rev. Federico Lombardi, said he isn't even sure of Benedict's title — perhaps "pope emeritus."
Since becoming pope in 2005, Benedict has charted a very conservative course for the church, trying to reawaken Christianity in Europe where it had fallen by the wayside and return the church to its traditional roots, which he felt had been betrayed by a botched interpretation of the modernizing reforms of the Second Vatican Council.
His efforts though, were overshadowed by a worldwide clerical sex abuse scandal, communication gaffes that outraged Jews and Muslims and, more recently, a scandal over leaked documents by his own butler. Many of his stated priorities as pope also fell short: He failed to establish relations with China, or reconcile with a group of breakaway, traditionalist Catholics.
There are several papal contenders in the wings, but no obvious front-runner — the same situation as when Benedict was elected after the death of John Paul. As in recent elections, some push is expected for the election of a Third World pope, with several names emerging from Asia, Africa and Latin America, home to about 40 percent of the world's Catholics.
The pope has clearly slowed down significantly in recent years, cutting back his foreign travel and limiting his audiences. He now goes to and from the altar in St. Peter's Basilica on a moving platform to spare him the long walk down the aisle. Occasionally he uses a cane.
As early as 2010, Benedict began to look worn out: He had lost weight and didn't seem fully engaged when visiting bishops briefed him on their dioceses. But as tired as he often seemed, he would also bounce back, enduring searing heat in Benin to caress a child and gamely hanging on when a freak storm forced him to cut short a speech during a youth festival in Madrid in 2011.
His brother, Georg Ratzinger, 89, said doctors recently advised the pope not to take any more trans-Atlantic trips.
"His age is weighing on him," Ratzinger told the dpa news agency in Germany. "At this age, my brother wants more rest."
Benedict emphasized that to carry out the duties of being pope, "both strength of mind and body are necessary — strengths which in the last few months, have deteriorated in me."
"After having repeatedly examined my conscience before God, I have come to the certainty that my strengths due to an advanced age are no longer suited" to the demands of being the pope, he told the cardinals.
In a way, it shouldn't have come as a surprise. Benedict himself raised the possibility of resigning if he were too old or sick to continue.
"If a pope clearly realizes that he is no longer physically, psychologically and spiritually capable of handling the duties of his office, then he has a right, and under some circumstances, also an obligation to resign," Benedict said in the 2010 book Light of the World.
But he stressed that resignation was not an option to escape a particular burden, such as the sex abuse scandal.
"When the danger is great, one must not run away. For that reason, now is certainly not the time to resign. Precisely at a time like this one must stand fast and endure the situation," he said.
When Benedict was elected in 2005 at age 78, he was the oldest pope chosen in nearly 300 years. At the time, he had already been planning to retire as the Vatican's chief orthodoxy watchdog to spend his final years writing in the "peace and quiet" of his native Bavaria.
On Monday, Benedict said he plans to serve the church for the remainder of his days "through a life dedicated to prayer."