Louis Decorsant (1866-1935) was a Catholic Priest known principally for promoting a form of devotion to the Immaculate Heart of Mary based on the mystical experiences of the Belgian Franciscan Tertiary, Berthe Petit.[1]
Decorsant was born in St Quentin, France, and trained as a lawyer, attainting the degree of Doctor of Law. When engaged to be married, and only 16 days after Berthe Petit (who at that time was unknown to him) had offered a prayer asking God to call a new soul to the priesthood, he suddenly decided to break his engagement and apply to become a Catholic priest. Following studies in Rome, he obtained a doctorate in philosophy and was ordained priest on 9 July 1893.[2]
As a priest, Decorsant served 15 years as a curate in Vincennes, France, until he was forced to take medical leave due to overwork. During this leave, in 1908, he made two pilgrimages to Lourdes where he first encountered Berthe Petit.[3] Later, he was instrumental in communicating some of her revelations to Pope Benedict XV via Cardinal Mercier, resulting in the Pope's explicit recommendation to seek the intercession of the "Sorrowful and Immaculate Heart of Mary" ('Cuore addolorato ed immacolato di Maria') in his May 1915 letter to the bishops of the world.[4][5] Decorsant was also a correspondent with Cardinal Bourne of Westminster in preparing a national act of consecration to the Sorrowful and Immaculate Heart of Mary in Lent 1917.[6]