Pope Francis spoke about the wisdom and knowledge of the faith older people can share with the young at a book presentation Tuesday.

"One of the virtues of grandparents is that they have seen many things in their lives," the pope said Oct. 23. "I advise [grandparents to have] a lot of love, a lot of tenderness… and prayers" for the young people in their lives who have left the faith.

"The faith is transmitted always in dialect. The dialect of the home, the dialect of friendship," he said.

Pope Francis answered a series of questions from both young and elderly people at the presentation of a book published in Italian and English, called "Sharing the Wisdom of Time."

It consists of interviews with older people from around the world and includes the responses of Pope Francis to 31 of the testimonies, as relayed in conversations with Jesuit Fr. Antonio Spadaro, editor of the Italian journal "La Civilta Cattolica."

Among those who asked a question was the film director Martin Scorsese, who recalled his childhood growing up in the Catholic faith and attending St. Patrick's Cathedral in New York City.

Scorsese said he was fortunate to have loving parents and a priest who became a mentor to him in his formative years. In a time when the world seems to be "marked by evil" and "we see the painful human failings of the institutional Church, how do we old people help young people stay in the faith? How can we help the Church in this endeavor?" he asked Francis.

The pope said that people must teach that cruelty is wrong, that torture "is the destruction of human dignity." He also emphasized the gift of tears, which he said is "human and Christian and softens the heart."

"And closeness between young people and old people," he said.

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To a question from a 26-year-old Italian woman about the "culture of waste," and the pressures of individualism and competition, he said, the most mature young people "are those who go on the way with service and risk."

He also said "a gesture of open and outstretched hand comes to my mind," encouraging youth to "get your hands dirty."