My main areas of research are Islamic religious thought and the history and theology of Christian-Muslim relations. These are largely expressed in the following current research activities:
Christian-Muslim Relations, a bibliographical history an AHRC-funded project, aims to compile a definitive history of works written by Christians and Muslims against and about one another in the period 600-1900. The outcomes are published by E.J. Brill, Leiden, in print online by Brill. By July 2013, 5 volumes appeared covering the period 600-1500. I head an international team of 25 specialists who are currently working on volume 6, covering the period 1500-1600.
He is Islam editor of The Encyclopaedia of the Bible and its Reception, which traces the reception of themes and figures from the Bible in Judaism, Christianity, Islam, world faiths, literature, music, art, theatre and film. Published by De Gruyter, Berlin, it will appear in 30 volumes over 12 years, of which 7 volumes have appeared.
He is managing editor of the Brill series The History of Christian-Muslim Relations and senior editor of the journal Islam and Christian-Muslim Relations.