He was a student at the Faculties of Law and Literature in Grenoble, receiving his Agrégation in History in 1922 at the age of 21, the youngest in France.

In Notre inquiétude his theme was humanity's loss of meaning and direction in an increasingly industrialized and mechanized world.

[1] Starting in 1931 he wrote mostly about Catholicism, advised by Gabriel Marcel with whom he shared membership of the Ordre Nouveau.

He helped disseminate its ideas in books in which it is often difficult to distinguish his personal reflections from the doctrines of the movement he had attached himself to, and which make him a leading representative of the intellectual ferment among non-conformists in the 1930s: Le Monde sans âme (The World without a Soul), Les annés tournantes, Eléments de notre destin.

From 1941 to 1944, he wrote Le peuple de la Bible (The People of the Bible) and Jésus et son temps (Jesus and His Times), the first of a series of works of religious history that would culminate in the monumental Histoire de l'Eglise du Christ (History of the Church of Christ) (1948–1965).