His research interests are: New Testament in its Jewish and pagan context; Dead Sea Scrolls, Apocrypha and Pseudepigrapha.

He was awarded his doctorate in Marburg in 1974 with a thesis on studies on the image of man in texts of the Qumran community entitled Studien zum Menschenbild in Texten der Qumrangemeinde.

[3] From 1977 to 1986, he was research assistant to the New Testament scholar Martin Hengel and deputy director at the Institute for Ancient Judaism and Hellenistic Religious History at the Eberhard Karls University of Tübingen.

He completed his habilitation at the University of Tübingen in 1986 under the title Studien zur paulinischen Anthropologie in Römer 7.

[4] From 1988 to 1993, he was Professor of Jewish Studies and New Testament at the Westfälische Wilhelms-Universität in Münster and Director of the Institutum Judaicum Delitzschianum.