It was one of the concluding acts of a nearly eight-year, scandal-dogged papacy that, Benedict said Wednesday, was filled with "light and joy" but also had its darker moments when "the Lord seemed to be sleeping."
A day after blessing the faithful for the last time as pope, Benedict will leave the Vatican by helicopter Thursday for the papal summer residence and his retirement will formally take effect at 8 p.m., when he will become the "pope emeritus."
After thanking the more than 100 cardinals collectively from a gilded throne in the Clementine Hall of the Apostolic Palace, the pope rose and greeted each of them individually.
Draped in a red and gold mantle lined with snow-white ermine, Benedict clasped the cardinals' hands as they removed their distinctive red skullcaps to greet him and kiss his ring.
Benedict told them, "I will be close to you in prayer" as they meet in coming days to choose his successor from their ranks.
"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.
Benedict will initially reside in Castel Gandolfo, a hilltop town outside Rome where popes have summered for centuries. He is expected to stay there for several months before returning to live at the Vatican in a convent whose gardens offer a perfect view of the dome of St. Peter's Basilica.
Many of the cardinals who lined up to bid farewell to Benedict had been appointed to their powerful positions as so-called princes of the church by him or his predecessor, John Paul II, and are thus seen as followers of his doctrinal conservatism.
Benedict shocked the world on Feb. 11 when he announced that, feeling his age and diminishing strength, he would retire, a dramatic step that sent the members of the Vatican hierarchy into a tailspin. He reassured the faithful Sunday that he was not "abandoning" the church, but would continue to serve, even in retirement.
In an emotional and unusually personal message Wednesday, his final public audience in St. Peter's Square, Benedict said that sometimes he felt that "the waters were agitated and the winds were blowing against" the church.
His retirement will bring changes in style and substance.
In comparison to the heavy ornate robes he wore to greet the cardinals, Benedict will don a white cassock and 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, which is expected to start by mid-March, will begin amid a swirl of scandal. On Monday, Cardinal Keith O'Brien, Britain's senior Roman Catholic cleric said that 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 O'Brien has recused himself.
On Monday, Benedict met with three cardinals he had asked to conduct an investigation into the "VatiLeaks" 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.
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. 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 condition of anonymity.