As Pope Francis has battled double pneumonia in hospital for nearly three weeks, talk of the 88-year-old pontiff's death or resignation has become almost commonplace. A few senior Catholic cardinals are talking openly about the possibility that Francis could follow his predecessor Benedict XVI and resign.

Time-honored rituals, drafted and refined over centuries, allow time for mourning and provide order at a dramatic moment of transition.

Pope Francis has been at the Gemelli Hospital in Rome for 18 days, having been admitted due to acute bronchitis that developed into bilateral pneumonia. Despite the challenging situation, there is a sense of calm and hope for the pope's recovery at the Vatican,