Video: Pope Benedict calls for peace at New Year mass The 84-year-old pope, marking the seventh Christmas and New Year holiday season of his pontificate, celebrated Mass for several thousand people in St Peter's Basilica on the day the Roman Catholic Church marks its annual World Day of Peace. As has become customary at papal events since October, the pope, who is believed to be suffering from arthritis in the legs, was wheeled up the central aisle of St Peter's Basilica standing on a mobile platform. The Vatican says it is to conserve his strength, allow more people to see him and guard against attacks such as one on Christmas Eve, 2009, when a woman lunged at him and knocked him to the ground. After the mass, the pope appeared at his window overlooking St. Peter's Square to deliver his Sunday noon message. He called for reconciliation and forgiveness in conflict areas. His official message for the World Day of Peace, which was issued last month, is sent to world leaders and international institutions such as the United Nations.