Instead of reading from his prepared homily, Pope Francis delivered an impromptu sermon to a packed St. Peter's Square for Palm Sunday Mass, which marked the beginning of Holy Week for the Roman Catholic Church.

The pope spoke for two and a half hours before he began making his way around the crowd of 100,000 Romans and tourists, Fox News reports.

Following the ceremony, Francis ditched his red vestments, which symbolized the blood of Jesus after being crucified, spoke with the cardinals of the church and started greeting his adoring fans, some of which came from Rio de Janeiro and Poland just to meet him. Francis posed for selfies with the young Brazilian tourists before hopping in the open-topped popemobile and reaching a group of young people from Poland who also wanted to take a selfie with him.

Before the ceremony, Francis blessed some olive tree branches that resembled the holy cross. Many people in the crowd tried to get their hands on those branches, or palm fronds, according to Fox.

The pope's message to the crowd on Sunday called on people, including himself, to examine their own lives to see how they're living and ask themselves "Where is my heart?"

"Has my life fallen asleep?" Francis asked in reference to Jesus's disciples who fell asleep right before Judas betrayed him. "Am I like Pontius Pilate, who, when he sees the situation is difficult, washes my hands?"

The Holy Week is the last week of lent for Catholics who vowed to give up certain items, delicacies or habits for 40 days and will culminate next Sunday with Easter. The following week, the city of Rome will canonize two previous popes, John Paul II and John XXIII, on April 27.

Francis announced Sunday that he will be traveling to South Korea during the summer for an Aug. 15 Asian youth event in Daejeon.