“We must beware of the man who abounds in eloquent nonsense, and so much the more if the hearer is pleased with what is not worth listening to, and thinks that because the speaker is eloquent what he says must be true.” Augustine of Hippo, On Christian Doctrine, IV. 5. 7.
In this section Augustine of Hippo, the famous Christian theologian from late antiquity, identifies the characteristics of a good teacher as eloquence and wisdom. Here he warns against those who speak eloquently but without true wisdom.