While extremely sensitive as to the slightest approach to slander, you must also guard against an extreme into which some people fall, who, in their desire to speak evil of no one, actually uphold and speak well of vice. If you have to do with one who is unquestionably a slanderer, do not excuse him by calling him frank and free-spoken; do not call one who is notoriously vain, liberal and elegant; do not call dangerous levities mere simplicity; do not screen disobedience under the name of zeal; or arrogance, of frankness; or evil intimacy, of friendship. No, my friends, we must never, in our wish to shun slander, foster or flatter vice in others: but we must call evil evil, and sin sin, and so doing we shall serve God's glory.
Source: Introduction to the Devout Life
Contributed by: Zaady