While neither cross nor icons are mentioned in the Qur’ān's critique of Christian doctrine and practice, from early Islamic times onward, the public display and honor given to both have led to moments of contention between Christians and Muslims living together in the world of Islam and beyond. The topic appears in the earliest records of Christian-Muslim relations and it became a staple point of argument in Muslim, anti-Christian polemics and in Christian, anti-Islamic polemics and apologetics. In his new book, Charles Tieszen traces the history of the controversy over cross veneration as a point of interreligious argument in both Christian and Muslim texts in Arabic, Syriac, and Greek, from the eighth century until the fourteenth century a.d. He discusses the topic thematically in the main chapters of the book, highlighting the issue more or less chronologically: the cross as an interreligious stumbling block, as an occasion for the charge of idolatry, as a standard of shame or honor, as a proxy for Christ, and finally as a marker for the orientation of Christian liturgical prayer. What is more, the author provides two appendices. Appendix 1 gives a brief sketch of the sources he has used and their Christian or Muslim author; and, in appendix 2 (160–167), is an abbreviated schematic guide to these same sources, noting their language, their date, their author, and the page numbers of their appearance in the now standard reference work David Thomas et al., eds., Christian-Muslim Relations: A Bibliographical History (11 vols.; Leiden: Brill, 2009–2017).

Like Charles Tieszen's earlier book, A Textual History of Christian-Muslim Relations: Seventh-Fifteenth Centuries (Fortress, 2015), which is essentially a chrestomathy of selections translated into English from Christian and Muslim controversial texts, Cross Veneration in the Medieval Islamic World is a very welcome addition to the sparse library of historical studies of Christian-Muslim relations within the world of Islam, including works of eastern Christian writers in Syriac and Arabic, who until recently have been virtually unknown among western Christians and especially among English speakers. Both books are ideally composed for use in undergraduate and graduate courses in college and university departments of both theology and religious studies, not to mention for the general reader.

In most texts of Christian-Muslim controversy in Arabic, cross and icon veneration appears as a minor topic, taken up after long discussions of more weighty issues such as the Christian doctrines of the Trinity and the Incarnation. But this seemingly minor topic having to do with the behavior of Christians in the public sphere of the World of Islam (Dār al-Islām) was nevertheless fraught with both political and religious significance, as Tieszen clearly explains. Politically, the display of the cross in particular, with its long history as a tropaeum (a Roman sign of military victory) and the Christian use of it as a communal emblem of identity, was seen as a direct challenge to Islamic political hegemony. Religiously, the public display and veneration of the cross and Christian icons together proclaimed the truth of religious doctrines challenged by the Qur’ān. The cross proclaims the death of Christ on the cross, a fact that a well-known verse in the Qur’ān (IV an-Nisā’ 157) was early-on taken by Muslim exegetes to deny that Jesus was ever actually killed or crucified; it was only seemingly so. The most common icons, those featuring Mary and/or her son Jesus, were reminders of the Christian belief that Jesus the Messiah, the son of Mary, was and is in fact the Son of God, a doctrine flatly contradicted in the Qur’ān. So the seemingly minor topic of Christian-Muslim controversy turns out, in fact, to have entailed the major point at issue between the two creedal communities, the truth about Jesus of Nazareth.

It is a feature of the genius of Tieszen's book that with his focus on the deceptively simple issue of what he calls “cross veneration” he introduces the reader not only to the major and minor religious issues in dispute between Christians and Muslims but also to the principal Christian and Muslim authors of the debate texts and the history of the development of the most common themes and modes of argument at play in their works over the centuries. This, in addition to the above mentioned appendices, charts, and indices, makes the book an ideal introductory text for the study of the history of Muslim-Christian relations within the World of Islam, a neglected topic of crucial importance for today's Christian-Muslim encounters in the wider world. Nevertheless there remain some questions for this reviewer.

Charles Tieszen says that his book has “two main goals: to tell the story of cross veneration as a theological and political idea in medieval Islamic milieus and to situate the function of this idea as an attempt to define Christian religious identity” (116). In my opinion, he has well achieved his first goal. As for the second, the effort to define Christian religious identity in response to the challenge of Islam is, of course, too broad a task to be accomplished simply by the defense of cross veneration. The apologetic imperative facing Christians living in the Islamic world necessitated a response to the Islamic critique of the major articles of the Christian creed and the practices of Christian worship across the board. In short, Arabic-speaking Christians living within the horizon of an Islamicate culture, which they shared with other non-Muslims, were faced with the task of elaborating within the purview of Islam a comprehensive Christian theology articulated in Arabic and expressed in terms calculated to defend the reasonableness of their beliefs. This broad accomplishment defined their creedal identity.