His first book,
Apologetik der Kirche, was published in 1835, and favourably noticed by Protestant critics. He was appointed, first, associate professor, then regular professor, lecturing on apologetics and moral theology, but he ultimately restricted himself to dogmatic theology. He became dean of the faculty in 1849 and, with
August Bisping,
Joseph Schwane, and others, established the faculty's reputation in the field of dogma. Kuhn numbers him among those who discussed theological matters philosophically, while Knöpfler regards him as belonging to the
Tübingen school.
Heinrich Brück, in his history of the Catholic Church in the nineteenth century, declares, "Berlage's writings excel in correct expression of dogmatic principles, in elegance of language, and in clearness of diction". As a lecturer he was concise and direct. He collected his studies in seven volumes,
Katholische Dogmatik, published 1839-64. ==Bibliography==