Pope Benedict XVI on Thursday called for "real renewal" in the Church at an emotional farewell with priests from his Rome diocese where he said he would be "hidden from the world" once he resigns.
"We must work for the realisation of the real Council and for a real renewal of the Church," the pope said in a rare off-the-cuff speech about his experiences as a young reformer at the Second Vatican Council of the 1960s.
"Even though I am retiring for prayer now, I will always be close to all of you and I am sure you will remain close to me even though I will be hidden from the world," the 85-year-old said as hundreds of priests cheered and applauded.
The pope remembered the "enthusiasm" of the Council, which changed the face of Roman Catholicism by overhauling archaic rituals like mass in Latin. Benedict has since turned conservative.
The speech came a day after outpourings of emotion at his final public mass in St Peter's Basilica, after saying Monday that his advancing age prevented him from fulfilling his duties.
Thousands of tearful priests, nuns and ordinary faithful applauded the outgoing pope at the Ash Wednesday mass, which marks the start of a period of penitence in the Christian calendar before Easter Sunday on March 31.
Cardinals in purple Lent vestments doffed their mitres as a mark of respect.
The pope waved and smiled at the crowd, appearing relieved following his momentous announcement, which will make him only the second pope to resign in the Church's 2,000-year history, and the first to do so in over 700 years.
His final homily was a hard-hitting one, condemning the "hypocrisy" of those who use their religion just for show. He also urged an end to "rivalry" and "divisions" within a Church beset in recent years by a series of scandals.
Many have speculated that health concerns are behind the move, pointing to a series of incidents in recent years.
The Vatican on Thursday confirmed a newspaper report that Benedict hit his head and bled when he got up in the night during his trip to Mexico last year but said it had no bearing on his decision.
On Tuesday, the Vatican also admitted the pope had routine heart surgery to replace the batteries in his pacemaker.
The Vatican has said it expects the Conclave of Cardinals -- the 117 cardinal electors who meet behind closed doors under Michelangelo's famous frescoes in the Sistine Chapel at the Vatican -- to elect Benedict's successor by Easter.
No firm date has been set but the conclave is expected to start between March 15 and March 19. There are signs that internal divisions could complicate reaching the two-thirds majority needed for a new pope.
Brazilian cardinal Joao Braz de Aviz told the Italian news agency ANSA of "tensions" between different personalities in the Vatican.
South African cardinal Wilfrid Fox Napier, who like Braz de Aviz is seen as a possible successor, said the Church was in a state of "profound crisis" and needed a new pope to bring about "spiritual renewal".
Napier also predicted that next month's conclave would last longer than the previous one in 2005, which took just two days to decide on Benedict.
The field so far appears wide open, with no clear favourite.
Napier said he would not rate candidates based on where they came from but indicated that the "balance" in the Church had shifted to the southern hemisphere, now home to most of the world's 1.2 billion Catholics.
"The determining factor is he must have the wisdom and energy to confront the challenges that await the Church in every corner of the globe," he told Italian daily La Stampa.
"Church institutions should help evangelisation, not slow it down. Too often we give an impression to the outside world of confrontations and careerism rather than serving the faithful.
"People, and young people in particular, are waiting for words of truth from the Church.... On sexuality and ethics there is a strong need for sense. We need a dialogue of truth," he added.
Benedict has said he will step down on February 28 at 1900 GMT and retire to a Vatican monastery, setting up an unprecedented situation in which a pope and his predecessor will live within a stone's throw of each other.
Adding to the unusual nature of the arrangement, Benedict's protege, Georg Gaenswein, will live with the former pope as his secretary while also working closely with the new pontiff as prefect of the papal household.
Vatican spokesman Federico Lombardi says Benedict -- who will revert to his previous name of Joseph Ratzinger -- could provide some kind of spiritual guidance for his successor, but his title is unclear.
"He will remain Benedict for us, that cannot change, but if we bump into him in the street I'm not sure what we'll call him," Lombardi said.