This book offers a comparative theological exploration of the challenges and opportunities presented by the Qur'anic representation of Christianity as the People of the Book, ahl al-kitab, in the Qur'anic commentary tradition. The research is divided into three parts. The first part explores the Qur'anic understanding of the People of the Book through traditional Islamic exegesis, known as tafsir, of four Islamic scholars whose work spans more than a thousand years. Part two takes a closer look at the pre-Islamic period, the occasion of revelation of the Qur'an as well as the Arabic speaking Christian response to Islam in the post-conquest period. Part Three explores the modern use of the term People of the Book by several scholars in the context of our increasingly interconnected and pluralist societies.