Benedict was a young theological expert at Vatican II, the 1962-65 meetings that brought the Catholic Church into the modern world with important documents on the church's relations with other religions, its place in the world and its liturgy.
Benedict has spent much of his eight-year pontificate seeking to correct what he considers the misinterpretation of Vatican II, insisting that it wasn't a revolutionary break from the past as liberal Catholics paint it, but a renewal and a reawakening of the best traditions of the ancient church.
He drove that point home on Thursday, blaming botched media reporting of the council's deliberations for having reduced the work to "political power struggles between various currents in the church."
Because the media's interpretation was more accessible than that of the council participants, that version fueled popular understanding of what the council was all about, Benedict said.
That led in the following years to "so many calamities, so many problems, really so many miseries: Seminaries that closed, convents that closed, the liturgy that was banalized," he said.
In what will be one of his final public remarks as pope, Benedict said he hoped the "true council" will be understood.
"Our job in this 'Year of Faith' is to work so that the true council, with the strength of the Holy Spirit, is truly realized and that the church is truly renovated," he told the priests.
Just hours earlier, Benedict delivered another pointed message during an emotional Ash Wednesday Mass in St. Peter's Basilica, his last public liturgy before he resigns.
In his homily, Benedict lamented the internal church rivalries that he said had "defiled the face of the church" — a not-too-subtle message to his successor and the conclave that will elect him.
Those rivalries came to the fore last year with the leaks of internal papal documents by the pope's own butler. The documentation revealed bitter infighting within the highest ranks of the Catholic Church, along with allegations of corruption and mismanagement of the Holy See's affairs.
Benedict took the scandal as a personal betrayal and a wound on the entire church. In a sign of his desire to get to the bottom of the leaks, he appointed a commission of cardinals to investigate alongside Vatican investigators.
His butler, Paolo Gabriele, was convicted and sentenced to 18 months in prison, although Benedict ultimately pardoned him.
Daniela Petroff contributed.
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