In keeping with the historic moment, Benedict changed course and did not produce his typical professorial Wednesday catechism lesson.
Rather, he made his final public appearance in St Peter's a personal one, explaining once again why he was becoming the first pope in 600 years to resign and urging the faithful to pray for his successor.
"To love the church means also to have the courage to take difficult, painful decisions, always keeping the good of the church in mind, not oneself," he said to thundering applause.
He recalled that when he was elected pope on April 19, 2005, he questioned if God truly wanted it. "'It's a great burden that you've placed on my shoulders,"' he recalled telling God.
During eight years, he said "I have had moments of joy and light, but also moments that haven't been easy ... moments of turbulent seas and rough winds."
But he said he never felt alone and thanked his cardinals and colleagues for their guidance and for "understanding and respecting this important decision."
Under a bright sun and blue skies, the square was overflowing with pilgrims and curiosity-seekers. Those who could not get in picked spots along the main boulevard leading to the square to watch the event on giant TV screens.
He told the tens of thousands of people jammed into the square today that he had decided to step down "for the good of the church".
St Peter's was overflowing and pilgrims and curiosity-seekers were picking spots along the main street nearby to watch the event on giant TV screens.
Some 50,000 tickets were requested for Benedict's final master class, but Italian media estimated the number of people actually attending could be double that.
The
pope greeted the crowds by making several rounds of the square as he
was cheered wildly. He stopped to kiss a half-dozen children brought up
to him by his secretary.
Benedict
thanked his cardinals, colleagues and ordinary faithful for their
support and for respecting his decision to become the first pope in 600
years to resign. He said that "to love the church means also to have the
courage to take difficult, painful decisions, always keeping the good
of the church in mind, not oneself."
With chants of
"Benedetto" erupting every so often, the mood - even hours before
Benedict was to arrive - was far more buoyant than during the Pope's
final Sunday blessing and recalled the jubilant turnouts which often
accompanied him at World Youth Days and events involving his
predecessor, Pope John Paul II.
"It's difficult - the
emotion is so big," said Jan Marie, a 53-year-old Roman in his first
years as a seminarian. "We came to support the Pope's decision, and feel
the air of the church."
Tomorrow, Benedict will become
the first Pope in 600 years to resign, a decision he said he took after
realising that, at 85, he simply did not have the strength of mind or
body to carry on.
After his general audience today, he
will meet cardinals for a final time tomorrow morning and then fly by
helicopter to the papal residence at Castel Gandolfo, south of Rome.
There,
at 8pm, the doors of the palazzo will close and the Swiss Guards in
attendance will go off duty, their service protecting the head of the
Catholic Church over - for now.
Many of the cardinals who
will choose Benedict's successor were in St Peter's Square for his
final audience, including retired Los Angeles Cardinal Roger Mahony,
object of a grass-roots campaign in the US to persuade him to recuse
himself for having covered up for sexually abusive priests. Cardinal
Mahony has said he will vote.
Vatican officials said
cardinals will begin meeting on Monday to decide when to set the date
for the conclave to elect the next pope.
But the
rank-and-file in the crowd today were not so concerned with the future;
they wanted to savour the final moments with the Pope they have known
for eight years.
"I came to thank him for the testimony
that he has given the church," said Maria Cristina Chiarini, a
52-year-old homemaker who travelled by train from Lugo, near Ravenna,
with some 60 members of her parish early today.
"There's
nostalgia, human nostalgia, but also comfort, because as a Christian we
have hope. The Lord won't leave us without a guide."