The Argentina-born Pope celebrated the Dec. 12 Mass to the sounds and rhythms of many of South America's indigenous peoples; the principal sung parts of the Mass were from the "Misa Criolla," composed 50 years ago by the late Ariel Ramirez. His son, Facundo Ramirez, conducted the choir that featured Patricia Sosa, a famous Argentine singer, as well as guitars and traditional instruments from the continent.

With St. Juan Diego's vision of Our Lady of Guadalupe in 1531, the Pope said, Mary "became the great missionary who brought the Gospel to our America."

In his homily, Pope Francis prayed that Mary would "continue to accompany, assist and protect our peoples" and that she would "lead all the children who are pilgrims on this earth by the hand to an encounter with her son Jesus Christ."

"Imploring God's forgiveness and trusting in his mercy," the pope prayed that God would help the people of Latin America forge a future of hope, development and opportunity for the poor and suffering, "for the humble, for those who hunger and thirst for justice, for the compassionate, the pure of heart, peacemakers and those persecuted for the sake of Christ's name."

Mary's "Magnificat," her hymn of praise to God, he said, proclaims that God "overturns ideologies and worldly hierarchies. He raises up the humble, comes to the aid of the poor and the small, and fills with good things, blessings and hope those who trust in his mercy."

Pope Francis said the day's reading from Psalm 66, with its "plea for forgiveness and the blessing of the peoples and nations and, at the same time, its joyful praise, expresses the spiritual sense of this Eucharistic celebration" in honor of Our Lady of Guadalupe, "for whom devotion extends from Alaska to Patagonia."

The dark-skinned image of Our Lady of Guadalupe traditionally believed to have been miraculously impressed on Juan Diego's cloak, the pope said, proclaimed to the indigenous peoples of the Americas "the good news that all its inhabitants shared the dignity of children of God. No more would anyone be a servant, but we are all children of the same Father and brothers and sisters to each other."

Mary did not just want to visit the Americas, the Pope said, the image on the cloak or "tilma" is a sign that "she wanted to remain with them."

"Through her intercession, the Christian faith began to become the greatest treasure" of the American peoples, Pope Francis said, a treasure "transmitted and demonstrated even today in the baptism of multitudes of people, in the faith, hope and charity of many, in their precious popular piety and in that ethos of the people who show that they know the dignity of the human person, in their passion for justice, in solidarity with the poor and suffering."