"Be neat, Philothea; let nothing be negligent about you. It is a kind of contempt of those with whom we converse, to frequent their company in uncomely apparel; but, at the same time, avoid all affectation, vanity, curiosity, or levity in your dress. Keep yourself always, as much as possible, on the side of plainness and modesty, which, without doubt, is the greatest ornament of beauty, and the best excuse for the want of it."
---St. Francis de Sales, Introduction to a Devout Life, Part Third, Ch. 25
"Frequent not the company of immodest persons, especially if they be also impudent, as is generally the case; ...these corrupted souls and infected hearts scarcely speak to any, either of the same or a different sex, without causing them to fall in some degree from purity; they have poison in their eyes and in their breath, like basilisks. On the contrary, keep company with the chaste and virtuous; often meditate upon and read holy things; for the word of God is chaste, and makes those also chaste that delight in it."
---St. Francis de Sales, Introduction to a Devout Life, Part Third, Chapter XIII.