Thousands packed into St Peter's Square to hear Pope Benedict XVI's farewell address and it may turn out to be his most significant speech.
He effectively confirmed rumours that all was not well in the Vatican, and that the first Papal resignation in 600 years was a direct result of the infighting, rivalry and factionalism at the heart of the Catholic church.
Europe Editor James Mates reports from the Vatican:
Pope Benedict XVI has held his final public audience, a day before he becomes the first pontiff to step down since the Middle Ages.
Pope Benedict said he resigned for the good of the church, not for the good of himself.
He said he was conscious of the "gravity" of the decision but took it with "profound serenity".
Benedict told pilgrims gathered in St Peter's Square to pray for the cardinals facing a weighty task choosing his successor.
The Pope said his papacy faced joy but also difficult moments, as he held his final public audience at the Vatican.
Benedict said he faced choppy seas and headwinds and at times "it seemed that the Lord was sleeping".
Pope Benedict has arrived at St Peter's Square, where huge crowds have gathered to watch his final public audience.