The Pope's remarks July 27 during the nighttime World Youth Day vigil marked his first reference to the demonstrations, which broke out in June to protest a range of grievances, including government corruption, unsatisfactory public education and health services, the high cost of public transportation and police brutality.

"In your young hearts, you have a desire to build a better world," the Pope told the young people. "I have been closely following the news reports of the many young people who, in many parts of the world and here in Brazil, have taken to the streets in order to express their desire for a more just and fraternal society."

But it is not enough to protest, he said.

"I encourage you -- in an orderly, peaceful and responsible way, motivated by Gospel values -- to continue to overcome apathy and offer a Christian response to the social and political concerns present in your countries."

And, he said, there is only one place to begin to make that change.

"Mother Teresa of Kolkata was once asked what needed to change in the church. Her answer was: 'You and I,'" and the same goes for changes in the world, the Pope said.