This collection of essays deals with the often neglected literary genre 'commentary' in ancient and medieval times. It is based on the work of the Bochum Graduiertenkolleg 237, where aspects such as definition, form and history of commentary texts, implicit commentation, pictures and paintings as commentaries were discussed. This volume presents a choice of 16 lectures which accompanied the colloquia from 1996. Introductions, but also special topics from the perspectives of theology, philosophy, classical philology, medical history, Arabic and Jewish Studies are given by the contributors. Great emphasis is laid on the interdisciplinary connection between these different points of view, for example by discussing the question on the impact pagan rhetoric had on Christian commentary texts. Further interest is focused on relevant literature - medicine, grammar, philosophy - and its commentaries.