Cardinals attend a mass led by poepe Benedict XVI for Ash Wednesday, opening Lent, the forty-day period of abstinence and deprivation for the Christians, before the Holy Week and Easter, on February 13, 2013 at St Peter's basilica at the Vatican. Pope Benedict XVI made his first public appearance on Wednesday since his shock resignation announcement, asking thousands of cheering pilgrims at the Vatican to "keep praying for me". TOPSHOTS/ AFP PHOTO / GABRIEL BOUYS