Self-referential discourse, i.e. the discourse of the Qurʾān about itself, is omnipresent in the Qur’anic text. Interestingly, it uses several strategies of argumentation and several rhetorical tools in order to persuade the listener or the reader to adhere to a specific understanding of what the Qurʾān is: an understanding leading to faith. Based on an extensive study of the self-referential discourse in the Qurʾān, this paper focuses on the importance of one of the rhetorical tools: “binarity.” This notion goes beyond the simple notion of “pairs” and is characterized by a clear-cut opposition ongoing in the whole text between elements of all kinds of domains and mainly in relation to biblical material. Contrary to what it may seem at first glance, “binarity” in the Qurʾān is far from being related to a dualist religious system. On the contrary, a close analysis shows that the use of “binarity” in the text emphasizes the exceptional character of the Qurʾān in relation to its divine origin. The function of “binarity” appears in all its rhetorical strength in the impression conveyed upon the listener or reader. Following the path of the works of contemporary scholars who used literary, structural, and argumentative analysis, this paper also aims at convincing the reader of the fruitfulness of rhetorical studies of the Qurʾān.