The changes Francis brought to the papacy were more than skin deep. He opened the church to the outside world in ways none of his predecessors had done before.

Pope Francis "rested well throughout the night" in the hospital, the Vatican says, and even met with Vatican officials to sign several documents linked to sainthood designations on Monday.

The Vatican has detailed laws and rituals to ensure the transfer of power when a pope dies or resigns, but not when he is sick