After personal searches in the field of atheism and Asian religions, at the end of the 40s, he will discover, through his texts Berdia y ev and his Lossky , the paternal theological thought of the Orthodox East. He was baptized an Orthodox Christian at the age of 31. He teaches History at the Lycée Luis - Le - Grand in Paris and, at the same time, for over 35 years, Comparative Theology and Moral Theology at the Institute of Saint Sergius. Honorary doctorate at the University of Louvain - La - Ne û ve , the Faculty of Theology in Bucharest and the University of Sacr é- Coeur in Connecticut , he also teaches at the Institute of Ecumenical Studies at the Paris Cathedral Center and the S è vres Center .
Olivier left a vast body of writing, which includes: Theology, Church History, Orthodox Spirituality and a great deal of writing, most notably in the magazine Contacts , of which he was Editor-in-Chief from 1959.