He was already familiar with this engagement during his stay in Rome. In parallel with his academic studies, Father Simon did not hesitate to hold pastoral responsibilities as assistant priest to many Catholic parishes in Europe. He assumed, from 1990 to 1991, the responsibility of ecclesiastic assistant of Don Andrea Santoro, parish priest of "Gesu di Nazareth” in the Zona Pietralata (Rome), and worked from 1991 to 1994 with Don Luigi Zangrilli, parish priest of " San Francesco of Assisi " in Cisterna, in the Italian province of the Latina.

That was not all. Episodically, he also assumed pastoral responsibilities in other parishes in Italy, Switzerland and Germany [" San Pietro Candelo " in Biella (Italy) during Christmas 1989, Easter 1990 and July 1990; " Parocchia di Introbio" in Lecco (Italy) during Christmas 1990; " San Martino " in Camorino (Switzerland) during Christmas (1991-1994), Easter (1990-1994) and July (1991-1993); parish of Aschaffenburg in Bavaria (Germany) in October 1992]. He also benefitted from some summer vacations to deepen his knowledge of the German language [stay at the Goethe - Institute in Murnau (Germany) in the summer of 1991, stay at the Gotz in Freiburg (Germany) in September 1992].

His pastoral efficiency during his stay in Rome allowed him to weave strong ties among his different European parishes and to achieve a libano-italian cooperation project for scouts. Upon his initiative, the Swiss parish of Camorino invited the Italian scouts group of Cisterna to celebrate Easter 1993 in their parish. The scouts accepted the invitation and came with their Lebanese chaplain to liven up the celebrations of the Ascension Day, Good Friday and Easter Sunday. Also upon his initiative, the scouts of Cisterna had invited 17 Lebanese scouts (eight of the Apostles’ Group and nine of the Group St. - Maron of Chekka) to a flying camp followed by a stationary camp in Italy in July 1992. It was an unforgettable moment for the participants.

Father Simon knew how to tie deep friendships also in Italy and Switzerland, relations that he will maintain after his return to Lebanon. Among those that proved to be the strongest, we mention: in Candelo, Mrs. Rita Pezzana, who Simon used to call "Mamma Rita " and considered her like a second mother, as well as the family Pessa (Paolo and Dianella with their daughter Francesca); in Camorino, the family Descritophoris (Mario and Maria Rosa with their daughters Ulda and Cinzia); finally, in Cisterna, the family Mercuri (Alberto and Maria Pina with their daughters Maria Dina, Claudia and Sara), a family who was especially close to his heart and with whom he used to stay every time he went on vacation to Italy after his definitive return to Lebanon on September 28, 1994.

Secular priest in the diocese of Jounieh (Lebanon), Father Simon was, starting October 15, 1994, the priest curate of Youssef Al - Andari in the parish of " Saint - Maron " in Haret Sakhr, then priest in this same parish from October 12, 1996, after the death of Father Al-Andari.

It is in Saint - Maron’s parish that Father Simon revealed his pastoral qualities. He gave back life and vigor to the feminine laic brotherhood of the Immaculate Conception and of Saint - Joseph, as well as the Marian union. Then he launched new parochial initiatives everywhere: he divided the parish into homogeneous pastoral zones each under a Saint's protection; created the "families Communities ", adapted version of the Notre Dame teams, promoted the life of couples and families within the parish, started the children’s Mass, the Youth Mass, the group of prayer; the parochial choir; the Children’s choir named " Choir of Charity " and the daily processions during the Marian month.

Along with his regular pastoral activities, Father Simon brought a particular care to the organization of high quality cultural activities inside his parish and the promotion of pastoral sharing among Catholic Churches of different rituals. He also accumulated several responsibilities outside his parish: He was member of the catechetic diocesan commission (1994-1999); member of the Youth diocesan commission (1994 -¼); member of the Ministerial Council (1994-1999); catechist in St. - John school of Okaybeh (1994-1998); spiritual animator in the Ste Famille Française college in Jounieh (1999-2001); chaplain of the Social Scouts Group in Jounieh (1998 -¼); dogmatic theology professor in St. - Peter and Paul’s center for the training of laymen in Azra (1996 -¼); lecturer at the preparation sessions for marriage in the diocese of Jounieh since their launching in 1996.