The Basilica of St. John Lateran, cathedral of the Diocese of Rome, was filled Tuesday with thousands of youths who had come to learn more about the two Bishops of Rome who will be canonized Sunday.

Both John Paul II and John XXIII will be canonized by Pope Francis April 27 at a Mass in St. Peter's Square.

Fr. Giovanngiuseppe Califano, a Franciscan and the postulator of Bl. John XXIII, opened the April 22 event by remembering some of Good Pope John's encounters with youth, for whom he searched "in the parishes of Rome, in the peripheries, hospitals and prisons."

"In those times we were all warned that the Pope used a new language, new gestures, and we felt his paternity. They were times of mercy."

"Above all, Pope John opened new horizons for the Church. The Second Vatican Council … had an inspiration from above, and he understood … we all had to build bridges of dialogue through which the Word of God passes."

Fr. Califano encouraged the youth to imitate the new saint, and affirmed that "the holiness of John XXIII is not impossible to imitate."

"The world loved the Pope for his goodness and his charity, but also for these surprising gestures in an elderly Pope who seemed transitional. The secret of his enduring youthfulness was his ability to renew their desire of belonging to God and to be fully realized in the light of God and his plan."

Monsignor Slawomir Oder, postulator for Bl. John Paul II's cause, then recalled the Pope in his years of seminary, and spoke about the moment of calling in the life of a Christian.

Finally, Fr. Fabio Rosini, vocations director for the Diocese of Rome, gave a catechesis.

Amid the thousands of youth, CNA spoke with Daniele Adani, a 20 year old student, who said, "Even though I didn't know John Paul II well, I remember the images in which he hiked through the mountains, and his talks … but what I remember most are the images of the funeral. That is where I really discovered the faith, and today he has become a very important person in my life."

Among the youth were also hundreds of adults who grew up with John Paul II, such as Laura Ganinberti, a 40 year old mother who explained to CNA that she came to the encounter with the youth "to return a favor of John Paul II."

"I belong to a generation that grew up with him, and knew he gave us values and a single horizon, the capacity of reading the whole truth in the message of the Cross, to go hand in hand, and to know the most beautiful news of the world: Christ is risen. Today I came with some youth of the parish, 20 or 30, and we said, 'How can it be that people of such different ages are going to the same destination?'"

For her part, Sister Carlota, 32, from the Congregation of Mary Queen of the Apostles for Vocations, explained to CNA that she met John Paul II during World Youth Day in Paris, and in Canada.

"It's beautiful to be able to pray to a person that you have met … a person whose face you know and whom you have met. It's beautiful to have this encounter during which the youth announce that faith is something beautiful and joyful."