He spent a happy summer mainly at Gohlis, near Leipzig, his jubilant mood being reflected in the Ode an die Freude; and in September of the same year he followed his new friend Korner to Dresden.
In1807-1808he delivered at Berlin, amidst danger and discouragement, his noble addresses to the German people (Reden an die deutsche Nation).
His greatest work, his commentary on the epistle to the Hebrews (Brief an die Hebrl er erldutert durch Einleitung, Ubersetzung, and fortlaufenden Commentar, in three parts, 1828, 1836 and 1840) won the highest praise from men like De Wette and Fr.
Becker; Im Anschluss an die Memoiren der H.
Koniggrdtz bis an die Donau (Vienna, 1906); Duval, Vers Sadowa (Nancy, 1907); Feldzugsjournal des Oberbefehlshabers des VIII.
In 1826 he removed as professor of theology to Leipzig, where, hitherto distinguished only as editor of Bardesanes, Marcion (Marcion's Evangelium in seiner ursprienglichen Gestalt, 1823), and Ephraem Syrus, and the joint editor of a Syrische Chrestomathie (1824), he came into great prominence as the author of a treatise, De rationalismi qui dicitur vera indole et qua cum naturalismo contineatur ratione (1827), and also of an Offene Erklarung an die Evangelische Kirche zuntichst in Sachsen u.
In the field of biblical criticism he wrote a Geschichte des Alten Bundes (1848-1855), Zur Theologie der Psalmen (1865) and Erkldrung des Briefs an die Hebrder (1869).