Love, says Jerome, the knowledge of the scriptures, and thou wilt not love the vices of the flesh.

The godlike Xenocrates showed this by the firmness of his reason, who was declared by the famous hetaera Phryne to be a statue and not a man, when all her blandishments could not shake his resolve, as Valerius Maximus relates at length.

Our own Origen showed this also, who chose rather to be unsexed by the mutilation of himself, than to be made effeminate by the omnipotence of woman--though it was a hasty remedy, repugnant alike to nature and to virtue, whose place it is not to make men insensible to passion, but to slay with the dagger of reason the passions that spring from instinct.
Again, all who are smitten with the love of books think cheaply of the world and wealth; as Jerome says to Vigilantius: The same man cannot love both gold and books.

And thus it has been said in verse: No iron-stained hand is fit to handle books, Nor he whose heart on gold so gladly looks: The same men love not books and money both, And books thy herd, O Epicurus, loathe; Misers and bookmen make poor company, Nor dwell in peace beneath the same roof-tree.
No man, therefore, can serve both books and Mammon.
The hideousness of vice is greatly reprobated in books, so that he who loves to commune with books is led to detest all manner of vice.

The demon, who derives his name from knowledge, is most effectually defeated by the knowledge of books, and through books his multitudinous deceits and the endless labyrinths of his guile are laid bare to those who read, lest he be transformed into an angel of light and circumvent the innocent by his wiles.