From 1976 to 1983 Achenbach studied Ev. Theology in Göttingen , Tübingen and Uppsala . From 1983 to 1986 he was a scholarship holder of the Luther Foundation and scientific staff at the University of Göttingen . Between 1986 and 1991 Achenbach completed the pastoral training and worked in the parish ministry. In 1989 he was with a thesis Deuteronomy at Lothar Perlitt to Dr. theol. PhD. From 1992 to 1994 Achenbach taught the Old Testament at the church university of the University of Medan / Pematangsiantar on the Indonesian island of Sumatra . After returning from Indonesia he held a repentent from 1995 to 1996 at the University of Mainz . In 1996, he joined the LMU Munich as an Academic Council , where he worked as a lecturer for Biblical Hebrew until 2005. In 2001 , he qualified there with a work on the emergence of the numerical book . In 2006, he received a call to the Westfälische Wilhelms-Universität Münster , where he has been a full professor since the winter semester of 2006/07 . Achenbach is one of the main applicants of the Cluster of Excellence "Religion and Politics in the Cultures of Pre-modernity and Modernity", which was established at the University of Münster in 2007, as well as a member of the Executive Board. Achenbach is also a member of the executive board and spokesman for the Center for History and Culture of the Eastern Mediterranean.

His research interests include Biblical legal history , the literary and editorial history of the Old Testament, the origin of the Pentateuch , the history of Judaism in the Achaemenid , the history of the Second Temple .