"We cannot help noticing the extent to which the 'Divine eloquence' of God is the eloquence of a Late Roman writer. For no one else would have made such a cult of veiling his meaning. Such a man lived among fellow-connoisseurs, who had been steeped too long in too few books. He no longer needed to be explicit: only hidden meanings, rare and difficult words and elaborate circumlocutions, could save his readers from boredom, from fastidium, from that loss of interest in the obvious, that afflicts the overcultured man. He would believe (with André Gide, among others) that the sheer difficulty of a work of literature made it more valuable—a sinister way of thinking in an age when educated men tended to form a caste, rebuffing the outsider by their possession of the ancient authors. Above all, the narrow canon of acknowledged classics had been charged with a halo of 'Wisdom': an intellectual agility quite alien to modern man, would have to be deployed constantly to extract the inexhaustible treasure that, it was felt, must lie hidden in so cramped a quarry."
Peter Brown, Augustine of Hippo: a biography (Berkeley, CA: The University of California Press, 1967), 259-260. Unfortunately, I can't think otherwise than with Augustine here: "such is the depth of the Christian Scriptures that, even if I were attempting to study them and nothing else, from boyhood to decrepit old age, with the utmost leisure, the most unwearied zeal, and with talents greater than I possess, I would still be making progress in discovering their treasures" (263, citing Ep. 137.3).