Pope Benedict XVI speaks to cardinals at Vatican

February 28, 2013 | 11:44 a.m. CST
In this image taken from video, Pope Benedict XVI delivers his final greetings to the assembly of cardinals at the Vatican on Thursday, hours before his resignation becomes official. Benedict urged the cardinals to work in unity and promised his "unconditional reverence and obedience" to his successor in his final words to his cardinals Thursday in a poignant and powerful farewell.

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