On May 14, 1922, Pier Giorgio joined the "Milites Mariae" club of the Italian Catholic Youth Society (the male branch of Catholic Action) at his parish of Crocetta, in Turin.
The motto of the Catholic Youth is: Prayer, Action, Sacrifice. Three words that summarize the daily commitment of its members. Pier Giorgio finds in them the mirror of his way of being.
He is truly a man of prayer, in constant conversation with God in community liturgies and in the privacy of his room.
He is a man of action, for whom words count for what they mean and, when they are useless, he chooses to remain silent; he knows that we will be judged by how much we have witnessed the Gospel in words and deeds, and he tries to be faithful to this task.
He is a man of sacrifice, who does not hesitate to give up something if it allows him to serve God, to do good.
For Pier Giorgio, Catholic Youth is feeling united by the same ideals, the same dreams, the same commitments. It is being able to help each other to be faithful, to grow.
Pier Giorgio strongly believes in associationism. In July 1923, when the GC club was founded in Pollone, the hometown of his parents where the Frassatis had a villa where they often went on vacation, he was asked to be the godfather of the flag.
He feels the importance of the national dimension of Catholic Youth. He is enthusiastic about large gatherings, and if he can, he takes part. He loves to build relationships with young people from distant regions. Faith is a bond stronger than any distance.
In 1921 he was in Ravenna for the congress of Pax Romana, then to Rome for the great congress of the GC, where he is the protagonist of the defense of the flag of the "Cesare Balbo" from the royal guards. In 1923 the Eucharistic congress of Genoa and the congress of the GC in Novara are some of the gathering opportunities offered to young Catholics in which Pier Giorgio can participate. Other times he will have to reluctantly give up: here too, choosing sacrifice.
Much enthusiasm reigned in the hearts of the good young people and more than a thousand brothers and sisters had come here to Pollone to honor these new flags. I believe that in Pollone there had not been such enthusiasm for several years: now the 2 circles are quite flourishing. Now much remains to be done and the most arduous work to be able to make the sister organizations flourish alongside these 2 circles, that is, that of the Catholic men and that of the Catholic women; but we must not be afraid and always have faith in the goodness of God who will give us the necessary Help to be able to make these 2 important branches of Catholic Action arise.
Letter to Antonio Severi – August 2, 1923
We must steel ourselves to be ready to sustain the battles that we will certainly have to fight for the fulfillment of our program and thus to give our country happier days and a morally healthy society in the not too distant future. But for all this we need: continuous prayer to obtain from God that grace without which our forces are vain; organization and discipline to be ready for action at the right moment and finally sacrifice of our passions and of ourselves, because without it we cannot reach the goal.
To the members of the «Milites Mariae» Circle – October 30, 1922