Pope Benedict XVI will lead an emotional Ash Wednesday mass in St Peter's Basilica amid lingering doubts over his reasons for announcing the first papal resignation for almost six centuries.
In a scheduling change prompted by the surprise declaration, which sent shockwaves throughout the Catholic world, the Vatican said the location of the annual service, usually held in a smaller church, would be changed in order to allow more worshippers to bid farewell to the outgoing pontiff.
The Vatican was forced to deny once again that the 85-year-old's decision to step down after an eight-year reign had been prompted by a specific health problem as it emerged he underwent secret surgery to replace the batteries in his pacemaker three months ago.
Responding to a report in the Italian daily Il Sole 24 Ore, according to which the operation had been carried out at the Pius XI clinic in Rome, the Vatican spokesman Federico Lombardi said the surgery had been "routine" and completely unconnected to Benedict's decision to step down.
Although known to some Vatican observers, the existence of the pacemaker had not been publicly acknowledged before. The pope, who suffered a haemorrhagic stroke in 1991, had had one fitted when still a cardinal, said Lombardi.
"It was a routine replacement of the batteries," he said, declining to give a specific date for the operation, from which Benedict was reported to have recovered well. "It is absolutely not a relevant procedure."
Benedict's health was not the only subject of speculation, however. The Italian daily Il Corriere della Sera claimed the "disturbing" findings of a recent report into the Vatileaks scandal may have played a role in his decision to step down. It did not elaborate.
Speaking in Germany, the pope's brother, Georg Ratzinger, admitted that the "indiscretions" of the affair, which resulted in the conviction of Benedict's butler for leaking confidential documents, had caused the pontiff particular worry.
But, speaking in the Vatican, Lombardi said that Benedict's move, which the pope himself put down to "advanced age" and declining mental and physical strength, could not be attributed to a particular issue or problem within the church.
Ahead of Benedict's resignation, at 8pm on 28 February, the Vatican is grappling with the immediate logistical challenges of the virtually unprecedented position in which it now finds itself. A conclave to pick a successor is due to begin within 15 to 20 days of Benedict's resignation but no specific date has yet been set.
It is not yet even clear what the pope will be called once he is pope no longer: whether he will be known, for instance, as "bishop of Rome, emeritus", and whether he will be addressed, as he is now, as Your Holiness, as a mark of respect.
Amid uncertainty over how much influence Benedict will continue to have, the Vatican has moved to quash any suggestion that he will somehow act as a competing authority to his successor. "I think if Joseph Ratzinger, Pope Benedict, still wanted to influence the church, he would remain as pope," said Greg Burke, senior communications adviser.
"I think he seriously wants to do what he has wanted to do for about 20 years, which is go study, read books and pray. And he's finally going to be able to do that. He's not that kind of person … by nature, he's not a conniver; he's not a schemer. He's not into that kind of stuff.
"He is a professor. He's a man of the church. I don't think it's a coincidence that he's going to be living in a monastery, essentially. I think he really does want a quiet life, and I would be very surprised if he tried to intrude in any way on the workings of the church."
Burke said restoration work on the Mater Ecclesiae convent in the Vatican had begun several months ago, with the specific aim of one day housing the pope. Lombardi said Benedict planned on spending his retirement in "prayer and reflection" and would have "no responsibility" for the governance of the church. Neither would Benedict have a role, he added, in the choosing of a successor. "He will not interfere in any way," Lombardi told journalists.
Though Benedict will not have a vote in the conclave, his conservative theological influence is nonetheless expected to be felt through the choices of those cardinals who will be voting, 67 of whom he appointed.
On Tuesday, one of the many men considered papabile said the time had come for a pope from the developing world. The 64-year-old Ghanaian Peter Turkson said the churches of Africa and Asia had produced "mature clergymen and prelates that are capable of exercising leadership also of this world institution".
Other candidates from the developing world include Odilo Scherer, the 63-year-old archbishop of São Paulo, and Óscar Andrés Rodríguez Maradiaga, 70, the archbishop of Tegucigalpa, in Honduras. They face stiff competition, however, from the likes of Marc Ouellet, the Québécois prefect of the Congregation for Bishops, and Angelo Scola, the Italian cardinal, who was appointed archbishop of Milan by Benedict in 2011.