Pope Francis Departs New York

Pope Francis walks the tarmac with Cardnial Timothy Dolan (2R) before boarding his flight from New York en route to Philadelphia from John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Nuns from the Monastery of the Precious Blood in Brooklyn, N.Y. are filled with anticipation as they spot the helicopter carrying Pope Francis to New York's John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Pope Francis waves at spectators gathered at JFK Airport to say goodbye to the pontiff as he departs for Philadelphia on Sept. 26, 2015. (credit: CBS2)

Pope Francis Departs New York

Pope Francis waves at spectators gathered at JFK Airport to say goodbye to the pontiff as he departs for Philadelphia on Sept. 26, 2015. (credit: CBS2)

Pope Francis Departs New York

Pope Francis waves to the hundreds of faithful who came to see him off as he boards his flight from New York en route to Philadelphia from John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Pope Francis waves at spectators gathered at JFK Airport to say goodbye to the pontiff as he departs for Philadelphia on Sept. 26, 2015. (credit: CBS2)

Pope Francis Departs New York

Pope Francis waves to the hundreds of faithful who came to see him off as he boards his flight from New York en route to Philadelphia from John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Pope Francis walks the tarmac with Cardnial Timothy Dolan (R) before boarding his flight from New York en route to Philadelphia from John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Pope Francis is greeted by nuns from the Monastery of the Precious Blood in Brooklyn, N.Y., who presented the pontiff with a gift of flowers before boarding his flight from New York en route to Philadelphia from John F. Kennedy International Airport on September 26, 2015. (Photo by John Paraskevas-Pool/Getty Images)

Pope Francis Departs New York

Pope Francis waves from the window of his plane as it takes off for Philadelphia from JFK on Sept. 26, 2015. (credit: CBS2)