Already in the years spent with Don Bosco, while he was director of the Salesian College in Trinità di Mondovì, Don Guanella knew more closely the Third Order of St. Francis of that Piedmontese fraternity and on 19 March 1877 he joined there, perhaps invited by Don Bosco, himself a Franciscan tertiary.
of Fr. Gabriel Cantaluppi
Even his first published writings are signed by him as a Franciscan tertiary. He took the attached duties seriously, as a boost of Christian and priestly commitment having as guide and model St. Francis of Assisi, towards whom he had sincere devotion, as well as he felt united with special affection to all the members of the three Franciscan Orders.
Also, on his return to Don Bosco, he managed to open his own institution in Traona in Valtellina in a former Franciscan convent with the adjoining Church of San Francesco; a return of theme and inspiration for him and for his mission.
Pope Leo XIII, also a tertiary, in 1882 published the encyclical "Desired concession” on the occasion of the seventh centenary of the birth of the Saint of Assisi, thus also favoring the rise of Institutes that came out of the Third Order, to respond to the needs of the new social classes.
This prompted don Guanella, parish priest in Pianello del Lario, to publish the volumes: A poor man of Christ e The Third Order of St. Francis and the encyclical of Pope Leo XIII to which he added Recent Rule of the Third Order of St. Francis, addressed especially to the people of the humble and simple people.
In the booklet The Third Order… his personal imprint also transpires in what concerns the spiritual content. Of St. Francis he underlines the poverty, humility, simplicity lived in the ardent contemplation of his Lord; they, instead, the poor mountain priest grasps the need to serve the poor, true images of Christ in continuous contact with God, in prayer and sacrifice.
Both booklets document not only his devotion, but a relationship of discipleship and imitation of the Saint, a sort of Franciscan line in his spirituality. And a profound knowledge of the Poverello appears, with long excerpts of quotations from the Saint's Letters, something quite rare at that time even for the Franciscans themselves. In fact he spent many of the moments free from parish duties in the Convent of Dongo, where in the library he found many useful aids for his publications, with particular interest in the life of Saint Francis, the Order, the Franciscan sources.
Sometimes he shared a frugal meal with the friars, always well received and esteemed. To express his fraternal gratitude, he too dedicated a pamphlet to the friars in 1883: An illustrious son of the Christian people, biography of the Franciscan native of Dongo and missionary bishop in China, Fra' Eusebio Maria Semprini. In the dedication he states that he wrote this pamphlet «to vent that spontaneous affection that I especially feel towards these religious reverends reformed in Dongo». When Semprini returned from China, after 32 years of absence, he hosted him both in Pianello and in Como and kept in correspondence with him by letter.
Also from Pianello was the Franciscan father Mario Bosatta, who, following the suppression of religious orders in 1866, had obtained permission from the superiors to be able to reside in his town and lived in the house adjacent to the church and rectory.
Father Gabriele Dell'Era, also a friar minor, a native of Pianello, had had Don Guanella as godfather of the priesthood and kept in correspondence with him for a long time.
In one of his many visits to the Convent of Dongo Don Guanella impressed a Franciscan novice Filippo Bonacina, who was struck by the veneration in which he was held by his fellow friars and, when he had to leave the Franciscan Order for various circumstances, became for sixty exemplary Guanellian priest.
In the foundation of the house in Como, Don Guanella also placed Saint Francis of Assisi among the patron saints, motivating the choice: "since everyone in the house is Franciscan tertiary".
Initially in the Rules she had invited her Sisters to enroll all in the Third Order during the Novitiate; but then the Holy See asked to abolish that obligation due to incompatibility of profession.
The mention of St. Francis always remained in every discussion of the theme 'poverty'; harmony and affinities should also be sought in the cheerful, cheerful and easy-going style required of the Guanellian religious, in the marked attention to the Eucharistic mystery, in the gaze of faith on creation, in the evangelical sense of fraternal relationships designed for the community, but above all in the key theme of fatherhood of God revealed in the prayer of the Our Father.
Once the house in Milan was opened, Guanella also began to attend the Franciscans of Sant'Antonio in Via Farini, in the Porta Volta area, where Father Lodovico Antonelli was provincial minister at the beginning of the century. It will be Father Agostino Gemelli, helped by don Guanella to overcome moments of strong religious crisis, in his testimonies to the processes for the beatification of don Guanella, to confess in what esteem the Franciscans held don Guanella so much as to propose him as a model of spiritual life and service to the Church for young friars in formation.