Pope Benedict XVI on Thursday called for "real renewal" in the Catholic Church at an emotional farewell ceremony with priests from his Rome diocese and told them he would be "hidden from the world" after he resigns at the end of this month.
"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, referring to 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 pontiff spoke of his personal experiences as a young reformer priest and the "enthusiasm" of the Council, which changed the face of Catholicism by overhauling archaic rituals like mass in Latin.
Benedict has since turned far more conservative in his outlook and on Thursday he condemned false expectations of radical change from the Council, saying they had created "a lot of misery".
As priests applauded and chanted "Long Live the Pope!", Benedict told them: "I will always be with you and together we will go with the Lord in the certainty that the Lord will be victorious."
The event came a day after emotional scenes at his final public mass in St Peter's Basilica, after saying Monday that his advancing age prevented him from keeping up with the modern world.
Thousands of tearful priests, nuns and ordinary faithful applauded the pope at the Ash Wednesday mass marking the start of Lent.
Cardinals thanked the outgoing pontiff for his service, doffing 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 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.
The Vatican has said it expects the Conclave of Cardinals, meeting behind closed doors under Michelangelo's famous frescoes in the Sistine Chapel, to elect Benedict's successor by Easter, which this year falls on March 31.
No firm date has been set for the conclave but it is expected to start between March 15 and March 19.
Signs of fierce divisions between cardinals have emerged in a tense lead-up to the conclave.
Brazilian cardinal Joao Braz de Aviz spoke in an interview with the Italian news agency ANSA of "tensions" between different personalities in the Vatican and said the Church administration was "anything but calm".
South African cardinal Wilfrid Fox Napier, who like Braz de Aviz is seen as a possible successor, meanwhile said the Church was in a state of "profound crisis" and needed a new pope to bring about "spiritual renewal".
The 71-year-old also predicted next month's conclave would last longer than the last one, which took just two days to decide on Benedict.
"We can come out of this profound crisis with a strong spiritual renewal like the one of St Francis who implemented a moral reform," Napier told La Stampa daily in an interview.
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 said.
"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.
Asked about the conclave, Napier said: "I don't think the white smoke will come so quickly this time around" - a reference to the plume of smoke emerging from the Sistine Chapel that indicates a new pope has been chosen.
At his weekly general audience on Wednesday, the pope told thousands of cheering supporters that he was resigning "for the good of the Church".
Benedict has said he plans to step down on February 28 at 1900 GMT and retire to a quiet life in 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.
Vatican spokesman Federico Lombardi says Benedict - who will revert to his previous name of Joseph Ratzinger - could continue to provide some kind of spiritual guidance for his successor, but his role and title remain unclear.
The final two weeks of his papacy will combine public engagements with private prayer, with next week given over to a spiritual retreat, a Lent tradition for the pope.
On the eve of his departure, the pope will hold an audience in St Peter's Square where thousands are expected to bid the contested but respected leader a final farewell.