Clues that led to pope's resignation announcement

With the benefit of hindsight, a series of clues leading up to Pope Benedict XVI's momentous resignation announcement this week suggest he had in fact been preparing the move for some time.

Benedict first mentioned he supported the idea of a pope resigning due to old age in an unusually candid book of interviews published in 2010 -- comments that made many wonder what he would do as he became increasingly frail.

"If a pope clearly realizes that he is no longer physically, psychologically, and spiritually capable of handling the duties of his office, then he has a right and, under some circumstances, also an obligation to resign," he told his interviewer for the book "Light of the World".

There were more recent moves too that indicated the pope was tying up loose ends and readying a delicate transition: he will be only the second pope to resign for health reasons in 2,000 years and the first in more than 700 years.

Here are some of the most salient hints picked up by Vatican observers:

-- In October, the pope celebrated the 50th anniversary of the Second Vatican Council and launched a Year of Faith -- an attempt to rekindle religious fervour amid rising secularism in the West and a key aim of his papacy.

"If today the Church proposes a new Year of Faith and a new evangelization, it is not to honour an anniversary, but because there is more need of it, even more than there was 50 years ago!," the pope said at the time.

"Recent decades have seen the advance of a spiritual 'desertification'. We see it every day around us. This void has spread," he added.

-- In November, the pope reached a milestone in his beloved career as an academic theologian by completing a trilogy on the life of Jesus Christ, which his closest advisers said was a personal project close to his heart.

-- In December, Benedict appointed his trusted personal secretary, fellow German Georg Gaenswein, to head of the pontifical household and elevated him to the title of archbishop, a move seen as a reward for a loyal servant.

The promotion also ensures Gaenswein will stay after his mentor steps down.

The previous prefect of the household, Monsignor James Harvey, was blamed in some circles for being too trusting of papal butler Paolo Gabriele who leaked confidential memos to the press in a perverse attempt to defend the papacy.

The "Vatileaks" scandal is seen by observers as an important factor in the pope's decision-making process as it affected him very personally.

The effective wrapping up of that scandal with a granting of the papal pardon for Gabriele just before Christmas could also be seen as closure.

-- In one of his most recent public speeches -- a 30-minute off-the-cuff speech to young seminarians in Rome on Friday, the pope spoke in very emotional terms about the challenges that faced Saint Peter, the first pope.

The pope said the apostle Peter's first letter in the Bible signalled the importance of having the papacy in Rome and said this idea carried with it a concept of university but also of the martyrdom that awaited the saint.

He also dwelled on the importance of a "chosen" people saying: "God thought of me, he elected me as a Catholic, as a carrier of the Bible, as a priest.

"I think it is important to reflect on this and return to this idea of election: I was elected, I was wanted, I respond," he said.

He concluded with a message of hope for a Church in troubled times saying: "The Church is always renewing itself, always being reborn."

-- Benedict's decision to keep on Secretary of State Tarcisio Bertone is now being seen as a possible attempt to ensure stability in the Church hierarchy during the transition.

Bertone, a powerful and divisive figure, reached the traditional age limit of 75 for cardinals of the Vatican in January 2010.

He will take over interim powers of governing the Church as soon as the pope steps down and until a successor is elected by a conclave of cardinals.