8 / 17

A policeman hold the Osservatore Romano newspaper in Rome

A policeman hold the Osservatore Romano newspaper in Rome February 11, 2013. Pope Benedict shocked the world on Monday by saying he no longer had the mental and physical strength to cope with his ministry, in an announcement that left his aides "incredulous" and will make him the first pontiff to step down since the Middle Ages. He will step down on February 28 and the Vatican expects a new Pope to be chosen by the end of March. REUTERS/Giampiero Sposito (ITALY - Tags: RELIGION) - RTR3DN7U

World reacts to Pope's resignation

Pope Benedict left the Catholic world in shock after becoming the first pontiff since the Middle Ages to resign his office, saying that failing strength had left him unable to lead the church through a period of relentless change and turmoil.