The first treatise written by Plotinus, On Beauty (Enn. 1.6), was admired among those Christian authors who were open to the influence of Platonic philosophy, in particular the Cappadocian Fathers. This could be due to a possible publication of the treatise before Porphyry’s editorial work for the Enneads. The presence of concepts of the treatise in their works is a sign of their interest in its rhetorical qualities and, at a deeper level, in the theoretical support that Plotinus’s thought could give to theological reflection. A possible reference to Plotinus’s treatise in Augustine, Conf. 10.6.8 is also discussed.