Emeritus Pope Benedict XVI is coming home to a new house and a new pope as an unprecedented era begins of a retired pontiff living side-by-side with a reigning one inside the Vatican gardens.

All eyes will be on Benedict's physical state Thursday as he is welcomed by Pope Francis. The last time he was seen by the public — March 23 — he appeared remarkably more frail and thin than when he left the Vatican on his final day as pope three weeks earlier.

The Vatican spokesman, the Rev. Federico Lombardi, has acknowledged the 86-year-old's post-retirement decline but insists he isn't suffering from any ailment and is just old.

Benedict will live in a converted monastery inside the Vatican gardens that has been renovated specifically for his use.