Francis seemed to endorse the mostly young demonstrators who have been taking to the streets here since last month to demand an end to corruption, excessive government spending and lack of basic services such as education and healthcare.
"The pope's telling us to listen to the voice of the streets, that was good," said Pedro Abramovay, a human rights activist and professor at the Getulio Vargas Foundation law school in Rio.
"It reinforces this important political moment in Brazil … when there is a great opportunity to reshape Brazilian democracy."
Of all his comments, Francis was perhaps most critical of the church's failure to stop the hemorrhaging of members to rival denominations, which he blamed on numerous factors, including an adherence to rigid rules and intellectualism over the "grammar of simplicity."
Brazil is the world's largest Catholic country. But, according to census data and a recent poll, the percentage of Brazilians who identify as Catholics has declined by 6 percentage points in just the last three years, to 57%.
And among 16- to 24-year-olds, the number of Catholics has fallen to 44%, while 38% say they are Protestants, which here almost always means membership in an evangelical church.
Andrew Chesnut, an author and professor of religious studies at Virginia Commonwealth University, said inclusion of the charismatic elements in Sunday's Mass was a positive step.
But the gesture is also overdue, in part because discussion of social justice, a favored Francis theme, remains esoteric for many of Latin America's poorest, while the evangelicals offer more concrete and immediate benefits, Chesnut said.
"This has the potential for sparking a revitalization of the church," Chesnut said of the pope's week in Brazil. "But nobody can stop the trend of pluralization of religions."
By nearly every account, the trip has been a roaring success for Francis, who has displayed his ease with pilgrims and his accessible messages, despite considerable logistical troubles such as failing public transportation that stranded worshipers and overly strained electrical and water systems.
"It's been like Teflon for the pope where the [organizational] problems are concerned," said Francis X. Rocca, Rome bureau chief for the Catholic News Service. "He goes back to Rome with his prestige definitely enhanced."
A mean task awaits him there.
He is forgoing the usual papal summer in the Castel Gandolfo outside Rome and is instead expected to shake up the Vatican's equivalent of a Cabinet with new appointments. Already, though, he seems to be meeting resistance, or at least controversy.
Two key appointments to a team meant to launch much-needed oversight of Vatican administration are being attacked in some Italian media circles as, on one hand, an indiscreet gay priest and, on the other, an indiscreet Twitter-user.
In comments to reporters on the flight to Rome, the pope said that he opposed any type of lobby that might try to influence his decisions. He was responding to a question about the so-called gay lobby inside the Vatican that some officials have alleged exists as a cabal of gay priests who run the Holy See.
He said it was important to distinguish between a lobby, which he did not approve of, and priests or other Catholics who might be gay.
“If a person is gay, seeks God and has good will, who am I to judge?” Francis said. “They should not be marginalized.”
The church has traditionally labeled homosexuality a “disorder,” and under Pope Benedict XVI, who resigned in February, men with “deep-seated tendencies” toward homosexuality were to be barred from the priesthood. Francis’ comments seemed to back away from an absolute ban.
On women, he repeated the church position that they cannot be priests. But he added women should not be “limited to being altar girls” and should be given expanded administrative roles in the church.
On the scandal-plagued Vatican bank, suspected of being used to launder millions of dollars, Francis said he would heed the advice of a five-member special oversight committee. But he said he did not know whether the bank could be saved or must be closed.
“Whatever the solution, it must have transparency and honesty,” Francis said.
Even on his lone day of rest here, after a flight of more than 15 hours, Francis was reported to be working on problems back in Rome. Maybe that is what he had in mind as he bade farewell to his native continent Sunday night.
"Already I am beginning to miss Brazil," he said. "I shall miss the warm and natural smiles."