VATICAN CITY -- Benedict XVI ceased to be pope at 8 p.m. local time (2 p.m. Eastern) Thursday when his resignation took effect, leaving the leadership of the Roman Catholic Church vacant while its leading clerics consider who should succeed him.
Benedict left the Vatican by helicopter on Thursday afternoon to spend the final hours of his scandal-dogged papacy and the first of his retirement at a summer residence used by popes for centuries. Onlookers in St. Peter's Square cheered, church bells rang and Romans stood on rooftops to wave flags to see him off as he flew from Rome to the summer residence at Castel Gandolfo, a hilltop town southeast of the city. More carillons heralded his arrival there, and he was greeted by a vivid contingent of silver-suited firemen, gendarmes in red capes, and bishops in black and pink.
Addressing cheering well-wishers from a window at the residence, he said: "Dear friends, I am happy to be with you! Thanks for your friendship and affection! You know this is a different day than others."
Earlier in the day, in one of his concluding acts, Benedict addressed a gathering of more than 100 cardinals who will elect his successor, urging them to be "like an orchestra" that harmonizes for the good of the Roman Catholic Church. From a gilded throne in the Clementine Hall of the Apostolic Palace, the pope thanked the cardinals collectively, and then rose to greet each of them individually.
Draped in a red and gold mantle lined with snow-white ermine, Benedict clasped the hands of each cardinal as they removed their red skullcaps and kissed the pope's ring. Benedict told them, "I will be close to you in prayer" as the next leader of the church is chosen. Many of them were appointed to their powerful positions as so-called princes of the church by Benedict or by his predecessor, John Paul II, and are seen as doctrinal conservatives in their mold. "Among you is also the future pope, whom I promise my unconditional reverence and obedience," Benedict told the cardinals, reflecting the concern among Vatican watchers about what it will mean to have two popes residing in the Vatican.
As pope emeritus, Benedict intends to reside in Castel Gandolfo for several months and then return to the Vatican to live in an apartment being prepared for him in a convent whose gardens offer a perfect view of the dome of St. Peter's Basilica.
He surprised many on Feb. 11 when he announced that, feeling his age and diminishing strength, he would retire, a dramatic step that sent the Vatican hierarchy spinning. He reassured the faithful on Sunday that he was not "abandoning" the church, but would continue to serve, even in retirement. In an emotional and unusually personal message on Wednesday, his final public audience in St. Peter's Square, Benedict said that he sometimes felt that "the waters were agitated and the winds were blowing against" the church.
His retirement will bring changes in style and substance. Rather than the heavy ornate robes he wore to greet the cardinals, Benedict will wear a simple white cassock, with brown shoes from Mexico replacing the red slippers that he and other popes have traditionally worn, the color symbolizing the blood of the martyrs.
The conclave to elect the next pope, expected in mid-March, will begin amid a swirl of scandal. On Monday, Cardinal Keith O'Brien, Britain's senior Roman Catholic cleric, said he would not participate in the conclave, after having been accused of "inappropriate acts" with several priests, charges that he denies. Other cardinals have also come under fire in sexual abuse scandals, but only Cardinal O'Brien has recused himself.
On Monday, Benedict met with three cardinals he had asked to conduct an investigation into a Vatican scandal in which hundreds of confidential documents were leaked to the press and published in a tell-all book last May, the worst security breach in the church's modern history. The three cardinals compiled a hefty dossier on the scandal, which Benedict has entrusted only to his successor, not to the cardinals entering the conclave, the Vatican spokesman said earlier this week.
On Thursday, Panorama, a weekly magazine, reported that the Vatican secretary of state, Cardinal Tarcisio Bertone, had been conducting his own investigation into the leaks scandal, including requesting wiretaps on the phones of some members of the Vatican hierarchy. That would be taking a page from the playbook of magistrates in Italy, where wiretaps are extensive.
The Vatican spokesman, the Rev. Federico Lombardi, said on Thursday that in the context of an investigation into the leaks, magistrates of the Vatican, not the secretary of state, "might have authorized some wiretaps or some checks," but nothing on a significant scale. The idea of "an investigation that creates an atmosphere of fear of mistrust that will now affect the conclave has no foundation in reality."
A shy theologian who appeared to have little interest in the internal politics of the Vatican, Benedict has said that he is retiring "freely, and for the good of the church," entrusting it to a successor who has more strength than he does. But shadows linger. The next pope will inherit a hierarchy buffeted by crises of governance as well as power struggles over the Vatican Bank, which has struggled to conform to international transparency norms.
Many faithful have welcomed Benedict's gesture as a sign of humility and humanity, a rational decision taken by a man who no longer feels up to the job.
As he stood near St. Peter's Square on Wednesday after attending the pope's last public audience, Vincenzo Petrucci, 26, said he had come to express "not so much solidarity, but more like closeness" to the pope. "At first we felt astonished, shocked and disoriented," he said. "But then we saw what a weighty decision it must have been. He seemed almost lonely."
Many in the Vatican hierarchy, known as the Roman Curia, are still reeling from the news. Many are bereaved and others seem almost angry. "We are terribly, terribly, terribly shocked," one senior Vatican official said, speaking on the condition of anonymity.
Alan Cowell contributed reporting from Paris.
Correction: February 28, 2013, Thursday
This article has been revised to reflect the following correction: An earlier version of the credit for the picture with this article showing a helicopter flying over St. Peter's Square misstated the surname of the photographer. He is Alberto Pizzoli, not Alberto Pizzolialberto.
This article originally appeared in The New York Times.