xvi. >> a couple years before pope benedict xvi resigns, pope benedict took a trip, and he laid his palium on the grave of celestine v, and a year and a half later he resigned. >> but despite the peaceful -- when he resigned, because of the violence and instability surrounding the resignation of benedict ix 250 years earlier, the new pope must make sure that celestine is never heard from again. >> after celest ne retired and boniface became pope, he felt it was dangerous to have two living popes. >> you can't have another pope knocking about and threatening the pope. immediately after celestine leaves, boniface has him attacked and locked up. >> he didn't want celestine talking to anybody, he didn't want him to be able to communicate with supporters, so essentially put him under house arrest to protect his legitimacy as pope. >> and so celestine dies in captivity. >> in the 13th century, however, a retired pope is not the only threat to a sitting pope's power. in a time when the lines between church and state are fluid, kings are just as threatening to papal power as previous popes.

the only pope who ever voluntarily did before benedict xvi. >> a couple years before pope benedict xvi resigns, pope benedict took a trip, and he laid his palium on the grave of celestine very. people didn't know it at the time but that might have been a signal because a year and a half later he too resigned his papacy. >> but despite the nature by which he resigned, because of the violence and instability surrounding the resignation of benedict ix 250 years earlier, the new pope must make sure that celestine is never heard from again. >> after celestine retired and boniface became pope, he felt it was dangerous to have two living popes. >> you can't have another pope knocking about and threatening the pope. immediately after celestine leaves the vatican, boniface has him attacked and locked up. >> he didn't want celestine talking to anybody, he didn't want him to be able to communicate with his supporters. so essentially put him under house arrest in order to protect his own legitimacy as pope. >> and so celestine dies in captivity. >> in the 13th century, however, a retired pope is n

xvi. >> a couple years before pope benedict xvi resigns, pope benedict took a trip, and he laid his palium on the grave of celestine v. people didn't know it at the time, but that might have been a signal because a year and a half later, he resigned. >> but despite the peaceful time when he resigned, because of the violence and instability surrounding the resignation of benedict ix 250 years earlier, the new pope must make sure that celestine is never heard from again. >> after celestine retired and boniface became pope, he felt it was dangerous to have two living popes. >> you can't have another pope knocking about and threatening the pope. immediately after celestine leaves the vatican, boniface has him attacked and locked up. >> he didn't want celestine talking to anybody, he didn't want him to be able to communicate with supporters, so essentially put him under house arrest to protect his legitimacy as pope. >> and so celestine dies in captivity. >> in the 13th century, however, a retired pope is not the only threat to a sitting pope's power. chch a state a fluid, es between kin

benedict's resignation really did do it voluntary and of his own vow. >> today pope benedict xvi lives in a quiet apartment in the vatican. he has passed the holy office peacefully down to pope francis, leaving the power struggles of the past behind. >> the biggest gift that ever happened to the papacy is pope benedict xvi resigning because he allowed the papacy not to become a trap. >> in terms of looking to the future, as any pope begins to get older or begins to have any difficulties, the question of resignation will be on the horizon. >> frances has also talked about resigning, and you don't know how serious he is. he's a mischievous man, he's old and he's got an agenda, and he's an old man, he may want to see that agenda out first. but he maybe. he watched the lesson of pope john paul ii collapse into hopelessness. >> it would be interesting if popes said, i've done my bit. someone else can have a go. >> in announcing his voluntary retirement, pope benedict has shaken the foundation of the papacy. if pope francis retires as well, a 2,000-year-old institution could be fundamentally

very soon, for the sake of the credibility and authority of the next pope, benedict xvi will, will, in his own words, be hidden from the world for the rest of his life. welcome back tuesday on the bbc. the two to newsday. think staying with us. another resignation, president trump's communications director hope hicks is to step down. it comes a day after she testified to congress. and, two royal couples on theirfirst official engagement together, talk about their plans for their charity. let's take a look at some front pages from around the world. the front page of the japan times features some brand new faces, ahead of the next olympic and paralympic games. that's because tokyo organisers have unveiled their official mascots. primary students picked futuristic and yet traditionally attired superheroes. the business standard has some good news for the indian economy, it's reached the number one spot again. the paper reports that the county outpaced its regional peers, including china last year. it has now become the fastest—growing economy. and finally, the china daily explains why s

. >> two weeks after benedict xvi resignation, pope francis is elected and the papal crown is handed from one man to the other. >> we have two popes, but only one is the pope. the problem with having two popes is that you have to decide who do you listen to? >> benedict was 85 when he resigned. he inherited the financial mess, he inherited the mess of sexual abuse, he inherited the administrative chaos. benedict resigned because he realized that these problems were simply too great for him. >> it's not like other human institutions. it's a creation, we believe, by god and this man is resigning from all of that. that's not what a pope is supposed to do. >> for 20,000 years, the legacy of st. peter has been a divine office passed down from one pope to the next. but can two men hold a legitimate claim to one godly office? >> "pope: the most powerful man in history" airs tonight at 10:00 on cnn. i just need some rest. i'm just worried about the house. and taking care of the boys. [ door slams ] he's still asleep. zach? zach?! [ dog barking ] ♪ [ sighs in relief ] zach! talk to me. it's