At the age of 17 he made his solemn profession in the Order of Friars Minor in the Province of San Francesco on Monte della Verna in Tuscany.

In the decade 1968–1978 he was Director of the Studium and for many years he was also a teacher in the International Theological Study of the Custody of the Holy Land.

In the academic year 1973-74 he wanted to celebrate the fiftieth anniversary of the foundation of the Studium and his work was rewarded with a significant letter of gratitude that Cardinal Jean Villot, Secretary of State, addressed to the Minister General of the Order on behalf of Pope Paul VI.

[3] Bagatti was responsible for numerous excavation campaigns in Italy, Palestine, Israel and Jordan; with his studies he made a decisive contribution to the progress of biblical archaeology in the field of Palestinology.

Among his writings are: His thesis on the Church of Zion, Jerusalem (1976) gained the support of Emmanuel Testa but is not generally accepted by the majority of archeologists.