Isaac Thomas Hecker (December 18, 1819 – December 22, 1888) was an American Roman Catholic Priest and founder of the Paulist Fathers, a North American religious society of men; he is named a Servant of God by the Catholic Church.Originally ordained a Redemptorist priest in 1849, with the blessing of Pope Pius IX, Hecker founded the Missionary Society of St. Paul the Apostle, now known as the Paulist Fathers, in New York on July 7, 1858.