(FILES) This file picture taken on July 4, 2010 shows Pope Benedict XVI looking on as he seats near the relics of one of his predecessors, St Celestine V, during a Holy mass on the occasion of the 800th anniversary of Celestine V's birth in central Garibaldi square in Sulmona. Pope Benedict XVI announced on February 11, 2013 his resignation, while the last pope to have abdicated the papacy is Celestin V in 1294. AFP PHOTO / FILES / ALBERTO PIZZOLI

(FILES) This file picture taken on July 4, 2010 shows Pope Benedict XVI (L) blessing the relics of one of his predecessors, St Celestine V, during a Holy mass on the occasion of the 800th anniversary of Celestine V's birth in central Garibaldi square in Sulmona. Pope Benedict XVI announced on February 11, 2013 his resignation, while the last pope to have abdicated the papacy is Celestin V in 1294. AFP PHOTO / FILES / ALBERTO PIZZOLI

(FILES) This file picture taken on April 28, 2009 shows Pope Benedict XVI (L) standing near the relic of Pope Celestine V after covering it with a stole during his papal visit at St Maria of Collemaggio church collapsed on April 6 after the earthquake in L'Aquila. Pope Benedict XVI announced on February 11, 2013 his resignation, while the last pope to have abdicated the papacy is Celestine V in 1294. AFP PHOTO / FILES / OSSERVATORE ROMANO

(FILES) This file picture taken on April 28, 2009 shows Pope Benedict XVI (R) covering the relic of Pope Celestine V with a stole during his papal visit at St Maria of Collemaggio church collapsed on April 6 after the earthquake in L'Aquila. Pope Benedict XVI announced on February 11, 2013 his resignation, while the last pope to have abdicated the papacy is Celestine V in 1294. AFP PHOTO / FILES / OSSERVATORE ROMANO

This picture shows a painting of Pope Celestine V by Italian painter Niccolo' Di Tommaso (Florence, Italy 1346-1376) in the museum of CatelNuovo in Naples on February 11, 2013. Pope Benedict XVI announced on February 11, 2013 his resignation, while the last pope to have abdicated the papacy is Celestine V in 1294. AFP PHOTO / ROBERTA BASILE