In Oration 38, Gregory describes the difficulty of contemplating God. He notes that, at the end, all one is able to do is to gather together variegated impressions “into one particular φαντασία of the truth” (38.7). For Gregory, this φαντασία is the only place on which to stand as the mind gazes “into the depth above” (38.8). A similar idea is also present in Oration 30.17 where Gregory argues that God cannot be named, contrary to Eunomius, and all one can do is create a weak φαντασία from the facts about him. Of the twenty-one times that Gregory uses φαντασία, eleven refer to God, while of the twenty-seven times he uses the verbal form (φαντάζομαι), eighteen have God as the object. At first glance, Gregory’s emphasis on φαντασία seems contrary to the antipathy of his contemporaries towards mental images (e.g. Evagrius of Pontus). Furthermore, and perhaps more importantly, φαντασία has a long philosophical history from Plato to Aristotle and the Stoics, as well as a significant rhetorical history in ἔκφρασις. Φαντασία as a concept was central to ἔκφρασις because through ἐνάργεια the orator was able to manipulate φαντασία stored in the mind. This short communication will examine Gregory’s use of φαντασία, both in theory and in practice, through the rhetorical devices of ἔκφρασις as his way of overcoming the epistemological problems for speaking truly about a transcendent God.