The religious, members of the Fraternity of St. Francis of the Providence of God, regard the pope's visit, scheduled for July 24, as the "confirmation of our path and of our calling," said Brother Isaac Prudencio, the hospital's vice director. "It's as if God descended upon earth and said, 'you are on the right path.'

"We are preparing for a great moment of evangelization inside the hospital," he said. "We are preparing people's hearts."

Yet, Brother Prudencio said the hospital was not overplanning the greeting for its guest.

"What we say at that time will be from our hearts," he said, noting that Pope Francis himself "tends to break protocol."

"We are waiting for his cue so that we can share our feelings with him," Brother Prudencio said.

The boyish-looking friar, who at 28 still wears braces on his teeth, was actually a senior member of the religious awaiting the pope at the hospital; many were barely out of their teens. That was fitting, of course, since the pope's visit to Brazil, the first international trip of his pontificate, will be for World Youth Day.

Pope Francis personally added the hospital to his Rio itinerary, which had been planned under his predecessor, Pope Benedict XVI.

The Vatican spokesman, Jesuit Father Federico Lombardi, told reporters in Rome July 17 that the pope intended the hospital, located in the working-class Tijuca district of northern Rio, to symbolize "all those working with poor, the marginalized and those struggling with addiction."

During his visit, Pope Francis will inaugurate a new wing of the hospital dedicated to the psychiatric treatment of drug addicts, including users of crack cocaine, who represent 3 percent of the population of Brazil, according to the World Health Organization statistics cited by the hospital. The city of Rio estimates there are 6,000 crack users in the city alone.

Representatives of other Catholic institutions in the same field have been invited to the event. Among them is Franciscan Father Hans Stapel, the German founder of the Fazenda da Esperanca, or Farm of Hope, a church-run drug rehabilitation center in rural Brazil that Pope Benedict visited in 2007.

Fifteen-year-old Carlos Francisco Tarige Britto, whose father overcame drug dependency in the Rio hospital, will present the pope with a St. Francis of Assisi sculpture, made by another former patient.

"It's incredible to me that he is coming to Brazil and that I will have a chance to meet him," Britto said. "I'm very emotional. On the spot, I don't even know if I'll be able to talk. I'll ask him for his blessing."