Sufism studies Ziedan's work on Sufism underscores not just the mystic introspective lineaments of Islamic Sufism, but, more importantly, its philosophical underpinnings. He has placed consistent emphasis on the study of
Ibn Arabi and
Abdul Karim al-Jili, regarded as two of the most important figures of philosophical Sufism in the history of Islam. His work on Abdul Karim al-Jili is seen by commentators as the most authoritative work in the field.
Islamic philosophy The most distinctive feature in Ziedan's study of Islamic philosophy is his attempt to uncover the origins of a strand of Islamic philosophical thought that, in his view, had not been influenced by
Hellenistic philosophy. He thinks that the parable of
Hayy Ibn Yaqzan, for instance, with its many versions and interpretations by such important figures as
Avicenna,
Ibn Tufayl,
al-Suhrawardi and
Ibn al-Nafis, is a source for understanding Islamic philosophy on its own terms. This view forms the basis of his re-editing of the complete philosophical parable of Hayy Ibn Yaqzan in his
Hayy Ibn Yaqzan: the Four Texts and their Authors. Ziedan's work as a public intellectual is reflected in several of his later works, including
Arabic Theology and Rationals Behind Religious Violence اللاهوت العربي وأصول العنف الديني which examines the dynamics behind the key ideas that shaped the faiths of
Judaism,
Christianity, and
Islam, and their links to each other and to the geography of the region.
History of Islamic medicine Another dimension to Ziedan's work is his study of the history of Islamic medicine, which draws him into the scientific realms of medicine, mathematics, astronomy, chemistry, and related topics. His scholarly career has included extensive explorations of the scientific heritage of Arab peoples throughout history, with special focus on medicine. He has studied the Arabic translations,
commentaries and annotations on
Hippocrates and
Galen especially. Furthermore, his studies on
Ibn al-Nafis and his critical edition of his grand medical encyclopedia (30 volumes)
al-Shamil fil Sina’a al-Tibbiyya catapulted Ziedan into being considered an Ibn al-Nafis expert.
Arabic manuscript preservation Ziedan sees cataloguing as an
ars maior that has not received the attention it deserves. According to him, cataloguing is the key to a panoramic view of a particular manuscript heritage. With this in mind, Ziedan produced some 20 manuscript catalogues using detailed descriptive cataloguing techniques rather than short, uninformative bibliographic records. His catalogues are mostly thematic, i.e. they are not general catalogues, but handle each theme of knowledge separately. ==Fiction==