Hermann Cohen born in Hamburg, Germany, on November 10, 1820, to an old Jewish family, showed an extraordinary talent for the piano from the age of four.

In 1833, at the age of twelve, he left Germany to live in Paris with Franz Liszt, of whom he became the favourite pupil. Years of wandering and moral unrest followed. For fourteen years, the young prodigy succumbed to the temptations of comfort and the heady effects of success. In May 1847, while directing a liturgical choir, he began a whole process of conversion through and in the worship of the Eucharist. Hermann founded the work of the Nocturnal Adoration of the Blessed Sacrament in France, which was founded in the Basilica of Notre-Dame des Victoires on December 6, 1848. He had been baptized the previous year, on August 28, 1847, on the feast of St. Augustine.

   In 1849 he entered the Order of Discalced Carmelites, recently re-established in France after the devastation of the Revolution. Ordained a priest (1851), the young religious actively engaged in the renewal of his Order. Since then his whole life was dedicated to an ardent love for the Blessed Sacrament and for the Virgin Mary, whom he called "Mother of the Eucharist".

Father Augustine-Mary of the Blessed Sacrament - such was his religious name - devoted himself to much successful preaching. Although he wished to hide forever in the "Desert" he had founded not far from Lourdes, two years before the apparitions, he had to travel throughout Europe at the behest of his superiors. They entrusted him with important missions: the restoration of the Lyon monastery (1859), of which he was made prior, the re-establishment of the Carmelite Order in England (1862), the foundation of the Bagnères monastery (1856), etc..

In 1868 he finally obtained permission to retire to his Pyrenees Desert, which allowed him to reconnect with the hermit origins of Carmel. As soon as he arrived, he was struck by a serious eye disease. The first of the children of Israel to make the pilgrimage to Lourdes, he was miraculously healed at the Grotto, ten years after the apparitions of the Virgin Mary.

Father Hermann was appointed Master of Novices of his Province in 1870. A few months later he left for Berlin as chaplain to French prisoners. The friend of saints (he was very close to St. Bernadette, the Curé of Ars and Blessed Pope Pius IX) dedicated himself to his brothers. During a smallpox epidemic, he contracted the terrible disease and died in Germany on January 20, 1871, a victim of his charity.