VATICAN CITY (NBC) - The pontiff rode through a large crowd in Saint Peter's Square as he arrived.
Easter is next Sunday, and the lead-up to it is considered the most important week in the Roman Catholic Church's calendar. On Palm Sunday, Christians remember Jesus' entry into Jerusalem before his crucifixion.
Sunday' mass followed a historic meeting Saturday between Pope Francis and the pope emeritus at the papal summer residence in Castel Gandolfo, Italy.
The pope emeritus has been living in Castel Gandolfo since he retired last month.
Pope Francis was elected on March 13th, so this was his first time celebrating Palm Sunday mass as the leader of the Roman Catholic Church.