Dixit ergo quidam eloquens, et verum dixit, ita dicere debere eloquentem ut doceat, ut delectet, ut flectat. Deinde addidit: Docere necessitatis est, delectare suavitatis, flectere victoriae [Cicero, Orator 69]. Augustinus, De Doctrina Christiana 4.74
Therefore an eloquent man has said, and he spoke true, that the eloquent man ought to speak so as to teach, to delight, to sway. Then he added: Teaching for necessity, delighting for pleasure, swaying for winning.
Thanks, dear reader, should you ever find me, for being my gadfly.