Johann Baptist von Hirscher (20 January 1788, Bodnegg – 4 September 1865) was a German Catholic theologian.
He was born in Alt-Ergarten, Bodnegg and studied at Weissenau monastery school, the lyceum of Constance, and the University of Freiburg. Ordained priest in 1810, he was for two years curate at Röhlingen; in 1812 he became a tutor in the theological faculty of Ellwangen; and in 1814 assistant professor of philosophy at the Ellwangen lyceum.
In 1817 he was elected to the chair of moral and pastoral theology in Tübingen University, where he remained twenty years. In 1837 he became professor of moral theology and catechetics at the University of Freiburg in the Breisgau, where, for a quarter of a century, he exerted a very great influence. He was made a canon in 1839, and dean of the chapter in 1850; after 1847 he was often sent as delegate of the university to the First Chamber of the Grand Duchy of Baden. His advanced age forced him to cease teaching in the summer of 1863.
Hirscher exerted a great influence in the domain of moral theology, homiletics, and catechetics. His book on Christian morality, published in 1835, ran through five editions. He defined Christian morality as the scientific doctrine of the effective return of man to the Divine filiation through the merits of Christ. In the earlier editions some of the expressions and opinions of Hirscher, owing to the influence of the day, were censured; he corrected them by degrees and Kleutgen considers that the last editions are perfectly orthodox. The book marked a reaction against rationalistic morality. Hirscher, always eager to dwell on religious truth, closely traced the moral act to a religious origin and a religious end, and he detested virtue that did not proceed from faith. Though not satisfactory from the point of view of confessors, Hirscher's work, as his apologist Hettinger says, had a salutary effect, and Hettinger himself made use of it to convert an unbeliever.
In homiletics, also, Hirscher's books marked a reaction against the half-rationalistic books of meditation written by the Swiss Zschokke, which were then widely read. Hirscher drew a distinction between false Aufklärung, which is purely negative and confined to combating superstition, and true Aufklärung, which is based on the Gospel. He published commentaries on the Gospels of Lent (1829), on the Gospels of each Sunday (1837), and on the Epistles of each Sunday. To this field of Hirscher's activity belong his "Geschichte Jesu Christi, des Sohnes Gottes und Weitheilandes" (1839); his "Erörterungen über die grossen religiösen Fragen der Gegenwart" (1846), which led to the development of Hettinger's vocation as an apologist; his "Leben der seligsten Jungfrau und Gottesmutter Maria" (1854); his "Hauptstücke des christlichen Glaubens" (1857).