As Pope Benedict XVI becomes the first pontiff to resign in nearly 600 years, BBC Religion and Ethics asks how the modern world has affected the papacy.
Although it has shaken the Catholic Church, Pope Bendedict XVI's resignation has been viewed by many church leaders and theologians as the honourable and sensible way to end a modern papacy.
As one British theologian put it: "Being leader of the Catholic Church requires an incredibly profound experience and wisdom, but also health and vitality."
This tricky combination also comes with the scrutiny of the 24-hour news cycle, global travel and communication.
One very revealing article, taken from Italian daily newspaper La Stampa, and translated and republished for Time Magazine in 2011, describes the typical papal day, starting at 7am with mass, followed by breakfast an hour later.
The article continues: "At 9am, the Pope goes into his private study, the one where he recites the Angelus prayer every Sunday, speaking from the window overlooking St Peter's Square.
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A week in the Pope's schedule
- Saturday: 11am Papal Mass, for the creation of new cardinals at the Vatican Basilica
- Sunday: 9.30am Papal Mass with new Cardinals. Followed at midday by reciting of Angelus prayer in St Peter's Square
- Monday: Audience with the new Cardinals at midday in Paul VI Hall
- Wednesday: General audience at 10.30am in Paul VI Hall
"He does his work in the study, where a consecrated laywoman, Birgit, helps him in her role as secretary and typist (she can read Benedict's tiny handwriting better than anyone else)."
According to the report, the Pontiff typically works until 11am, when audiences, or meetings, begin. Meals, it seems are always prompt; lunch is served at 1.15pm.
The Pope takes time each day for a "brief stroll in the roof garden" and some rest, then returns to his private study at 4pm, where he says the rosary and resumes his work.
The article, written for La Stampa's Vatican Insider section by Andrea Tornielli reports: "After a prayer, dinner is served at 7.30pm, in time to watch the 8pm newscast on RAI, the Italian state broadcaster.
"An hour later, the Pope says good night and retires, though he works some more before going to sleep."
So a Pope's working day is very full, and this is within a calendar packed with ceremonial "set pieces", official visits and travel, explains Professor Paul D Murray, director of the Centre for Catholic Studies at Durham University.
"There is the Wednesday public audience, the Sunday recitation of the Angelus and homily, a host of private audiences with visiting groups of bishops from around the world making their formal 'ad-limina' visits to Rome every five years, with visiting heads of state, political leaders, dignitaries, and religious leaders of other traditions," he adds.
"So there's a lot of meet and greet stuff, plus public speaking events."
On top of this, Pope John Paul II, Benedict XVI's predecessor, created the phenomenon of the "Papal road show", which Pope Benedict tried to maintain.
"That notion of the Pope taking Rome around the world is a very recent thing," says Prof Murray. "Before John Paul II, papal visits around the world were highly unusual."
Pope Benedict XVI actually cut down on his international travel commitments in 2012, but he has still been on three international visits, including trips to Mexico, Cuba and Lebanon, in the last 12 months.
Globalised church
The Roman Catholic Church is clearly no longer the sovereign power throughout Europe that it was during the Medieval period, and this shift has changed but not reduced the responsibilities of the presidential role of Pope.
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In quotes: Modern pressures on a Pope
- Vatican spokesman Federico Lombardi said that, with age, the Pope feels "he has less strength physically and mentally to cope with the challenges in the world of today for the government of the Universal Church"
- Lombardi stressed that the Pope was not suffering from depression or particular ailments but, "as it is normal for an elderly person, he is experiencing a phase of decline in his strength"
- The Vatican spokesman also said that Pope Benedict's resignation was not a binding choice for future popes, as "each personal situation is unique".
"While you might say the sheer power of papacy has decreased in the modern period, the nature of the job has not decreased in size - far from it," says Prof Murray.
An "information explosion" and modern forms of transport have brought the rest of the Roman Catholic church within easy reach of Rome.
Life in the limelight of media coverage is also unavoidable, and something that Benedict XVI did embrace; he was the first Pope on Twitter and the first on the BBC's Thought for the Day.
Enrico dal Covolo is a bishop and Dean of the Pontificia Universita Lateranense, otherwise known as the Pope's University, in Rome.
He acknowledges that modern communication - social media in particular - has brought new pressure on the Pope to engage with lay Roman Catholics.
"The Pope is very open towards what makes the church a living presence in the world," he tells the BBC.
"Even his Twitter account, which has been criticised by many and has also been targeted by insults, is the proof of this presence that the church expresses in the physical as well as in the digital world."
But these contemporary challenges are just small parts of the powerful presidential role of governing the Roman Catholic Church.
Power and influence
"In the middle ages, the Pope probably had less control of dioceses in other countries at the level of detail that can be exercised today," says Prof Murray.
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For Catholic Christians, the Church is not a multinational bureaucratic mechanism for the salvation of souls, it is a unified body whose many members receive and use God's countless gifts to build communities of love after the example of Jesus Christ.
In this ancient vision, the Pope's work - just like that of clergy or bishops - is a political act focused upon fostering the life of love within the given community as much as possible.
To speak the language of love will appear sentimental in the midst of the hard and unbending world of corporate capitalism, but in a more ancient theological perspective, love is the most solid of all realities such that the Pope's vocation must be at once a spiritual and political ministry.
Theologian's view: An ancient vision within a modern role
The ancient office of Pope was always a strange combination of institutional director and spiritual father.For Catholic Christians, the Church is not a multinational bureaucratic mechanism for the salvation of souls, it is a unified body whose many members receive and use God's countless gifts to build communities of love after the example of Jesus Christ.
In this ancient vision, the Pope's work - just like that of clergy or bishops - is a political act focused upon fostering the life of love within the given community as much as possible.
To speak the language of love will appear sentimental in the midst of the hard and unbending world of corporate capitalism, but in a more ancient theological perspective, love is the most solid of all realities such that the Pope's vocation must be at once a spiritual and political ministry.
The modern Catholic church is still very centralised. At the very least, Rome has to "sign off" on every major decision.
The Pope oversees the appointment of bishops around the world. "[He is], in fact, the major initiator of significant formal decisions within Catholicism," says Prof Murray.
"[The papacy is] effectively both the primary and the ultimate seat of governance and authority in the Roman Catholic Church."
Prof Murray explained that there have been calls for this structure to be reformed for more than 50 years in the direction of greater two-way collaboration, or "effective collegiality", with the bishops around the world, representing the dispersed authority and experience of the Church.
Since Pope Benedict XVI has resigned on grounds of what is required for the healthy governance of the Church, his stepping down may prompt fresh discussion as to how Roman Catholic bishops might be drawn more fully and more effectively into this responsibility.
Whatever the lasting effects on the way the church is governed, Pope Benedict XVI's resignation has triggered a great deal of admiration as well as surprise.
Bishop dal Covolo concludes: "His every action, including the latest, demonstrate his moral stature and what I define as a holy lucidity in making such a difficult choice."
Resignation, dal Covolo says, was a "sublime act of love".
