Before another ocean of Catholic youth on Rio de Janeiro's famed Copacabana beach -- dubbed for the occasion "Popeacabana" -- Francis on Sunday delivered another simple, pastoral message, expressed in three key charges he delivered: "Go," "Don't be afraid" and "Serve."
Sunday was the final day of the July 23-28 World Youth Day, and Francis celebrated the concluding Mass before a crowd estimated at 3.2 million by the local mayor's office.
Over the weekend, turnout for Francis' first overseas trip has rivaled that for John Paul II's initial outing in 1979 to the Dominican Republic and Mexico, when he drew an estimated 10 million to 15 million over the course of the journey. The experience suggests a memo to future popes: If you want your debut to be a smash, at least in terms of crowds, head to Latin America.
In his homily Sunday morning, Francis urged the participants in World Youth Day to carry its impact with them back home.
"The experience of this encounter must not remain locked up in your life or in the small group of your parish, your movement, or your community," the pope said. "That would be like withholding oxygen from a flame that was burning strongly."
He insisted that the missionary imperative in the church isn't optional.
"Jesus did not say: 'If you would like to, if you have the time,' but: 'Go and make disciples of all nations,' " the pope said.
"The church needs you, your enthusiasm, your creativity and the joy that is so characteristic of youth," Francis told the youth.
The pope also urged priests to promote the role of young people in the church not just this week, but continually.
"Continue to accompany them with generosity and joy, help them to become actively engaged in the church; never let them feel alone," he said.
Being a missionary, Francis said, means living a life of service to others.
"Evangelizing means bearing personal witness to the love of God," he said. "It is overcoming our selfishness; it is serving by bending down to wash the feet of our brethren."
Appealing to the idealism of youth, Francis told them their Christian faith is the key to building a better world.
"Bringing the Gospel is bringing God's power to pluck up and break down evil and violence, to destroy and overthrow the barriers of selfishness, intolerance and hatred, so as to build a new world," he said.
On Sunday afternoon, Francis will deliver a much-anticipated speech to the coordinating committee of the Episcopal Conference of Latin American (CELAM) and speak to a group of World Youth Day volunteers before a farewell ceremony at the Rio de Janeiro airport. He's scheduled to land Monday in Rome at roughly noon local time.
(Follow John Allen on Twitter: @JohnLAllenJr)