Bernard was educated as a priest in Rome and received his ordination in Reims by Cardinal Thomas-Marie-Joseph Gousset (1792–1866).

First a parish priest in the French Ardennes for a couple of years, he arrived in Norway in 1856, where he was put into service in the Catholic North Pole Mission (Praefectura Apostolica Poli Arctici).

Together with Jean-Baptiste Baudoin (1831–1875), Bernard was the first Catholic priest to serve in Iceland after the Reformation, where they built a small chapel at the Landakot farmstead near Reykjavík.

On April 5, 1869, Bernard was appointed Prefect Apostolic of Norway and Lapland with residence in Trondheim.

He was followed by the Luxembourg priest Johannes Olav Fallize (1844–1933),[3] from 1892 Titular Bishop of Elusa, under whom the mission steadily developed, although not yet large.