Pope Benedict XVI delivers his blessing during his last Angelus noon prayer, from the window of his studio overlooking St. Peter's Square, at the Vatican, Sunday, Feb. 24, 2013. Benedict XVI gave his pontificate's final Sunday blessing from his studio window to the cheers of tens of thousands of people packing St. Peter's Square, but sought to reassure the faithful that he wasn't abandoning the church by retiring to spend his final years in prayer. The 85-year-old Benedict is stepping down on Thursday evening, the first pope to do so in 600 years, after saying he no longer has the mental or physical strength to vigorously lead the world's 1.2 billion Catholics. (AP Photo/Andrew Medichini)