Macrobius, Saturnalia 5.14-15
“Has it been proved to you that Vergil cannot be understood by someone who is ignorant of the sound of Latin and is equally distant to one who has not drunk Greek learning deep with the fullest thirst?
If I did not fear making you antsy, I could fill huge volumes with the material he translated from the most obscure Greek teachings. But these assertions are enough to support the thesis I have proposed.”
probatumne vobis est Vergilium, ut ab eo intellegi non potest qui sonum Latinae vocis ignorat, ita nec ab eo posse qui Graecam non hauserit extrema satietate doctrinam?
nam si fastidium facere non timerem, ingentia poteram volumina de his quae a penitissima Graecorum doctrina transtulisset implere: sed ad fidem rei propositae relata sufficient.’