While speaking to his fellow Argentines Thursday, Francis said Catholics should make a concerted effort to get outside their own worlds.
"I want to see the church get closer to the people," he told them. "I want to get rid of clericalism, the mundane, this closing ourselves off within ourselves, in our parishes, schools or structures, because these need to get out."
His final message: "Don't forget: make trouble."
In his own way, he lived those words as the archbishop of Buenos Aires, Argentina, before being selected as pope in March.
Then known as Jorge Mario Bergoglio, the future pope largely abandoned the kinds of luxuries favored by other high-ranking church officials. He rented out the archbishop's luxurious suburban mansion, living instead in a spartan room in a downtown church office building. He also rode subways and buses around town rather than keep a chauffeur.
Francis' visit to a Rio slum on Thursday wasn't his first such venture. He made regular unescorted trips to dangerous slums as archbishop and saw to it that every major "misery village" in Buenos Aires had a chapel and a priest to spread the Lord's word.
He also encouraged young people and the laity to take on leadership roles in parishes that were previously held by priests, so that church members would have much more say in what happens in their communities. Though the Catholic Church openly supported Argentina's 1976-1983 dictatorship, Francis later approved sainthood investigations for priests who were killed by the military government.
Yet biographer Sergio Rubin said Francis the archbishop also had a very keen sense of politics and took care to act prudently, choosing his battles and avoiding challenging superiors in ways that would backfire.
He wasn't so gleeful and devoted to the crowd, seemingly mindful that he didn't yet have the power to make a big splash in the church, according to an Argentine Catholic official who asked not to be identified because he wasn't authorized to talk publicly about church politics.