An important and disputed topic in later medieval thought was the question of whether theology is a science in the sense that Aristotle articulated in the Posterior Analytics. However, as I hope to show, Aristotle's Rhetoric also influenced the debate in important ways, as did the writings of Augustine. My paper will explore Giles of Rome's understanding of whether theology is a science. As the first theologian belonging to the Order of the Hermits of Saint Augustine to hold a chair at Paris in the late thirteenth century, as well as the author of an important commentary on Aristotle's Rhetoric, Giles's understanding of the scope and nature of theology is unique. In particular, I will look at whether there is an evolution in Giles's thought from his characterization of theology as a type of rhetoric in the early Reportatio, to his understanding of theology as a so-called affective science in the slightly later Ordinatio to Book 1 of his commentary on the Sentences and, if so, what is motivating such a change in emphasis.