Pope Benedict XVI has told tens of thousands of people packed into St. Peter's Square that he is aware of the "gravity" of his decision to step down.
Benedict, during his final general audience on February 27, also said he was stepping down not for his own good but for the good of the Roman Catholic Church.
The 85-year-old Benedict will formally step down on February 28, the first pontiff to do so in nearly 600 years.
In his last address, he told the faithful of the "joys" but also the difficulties of his eight-year papacy when the church faced sexual-abuse scandals and allegations of high-level corruption.
Cardinals meeting in a secret conclave are expected to elect Benedict's successor in time for the Easter holiday at the end of next month.
Based on reporting by AP and AFP