"Do not be rash in judging the deeds and words of others, and do not entangle yourself in affairs that are not your own. Thus, it will come about that you will be disturbed little and seldom." Source: Thomas a’ Kempis, The Imitation of Christ, Dover Thrift Editions, 1940.
"If a word, we are like the Paphlagonian partridge, which has two hearts; for we have a very tender, pitiful, easy heart toward ourselves, and one which is hard, harsh, and strict toward our neighbor. We have two scales, one wherein to measure our own goods to the best advantage, and the other to weigh [...]
"If you have eyes for the shortcomings of your neighbor and not for your own, no feeling of mercy will arise in you but rather indignation. You will be more ready to judge than to help, to crush in the spirit of anger than to instruct in the spirit of gentleness. 'You who are spiritual, [...]
"We take others to task for small mistakes, and overlook greater ones in ourselves. We are quick to feel and brood over the things we suffer for others, but we think nothing of how much others suffer from us. If a man would weigh his own deeds fully and rightly, he would find little cause [...]
"From rash judgments proceed mistrust, contempt for others, pride, and self-sufficiency, and numberless other pernicious results, among which stands forth prominently the sin of slander, which is veritable pest of society." Source: St. Francis de Sales, Introduction to the Devout Life, Random House, Inc., 2002.
"Are we never, then, to judge our neighbor? you ask. Never, my child. It is God Who judges criminals brought before a court of law." Source: St. Francis de Sales, Introduction to the Devout Life, Random House, Inc., 2002.
"When a just man cannot see any excuse for what is done by a person in whose general worth he believes, he still refrains from judging him, and leaves all to God’s Judgment." Source: St. Francis de Sales, Introduction to the Devout Life, Random House, Inc., 2002.
"And so ought we always to judge our neighbor as charitably as may be; and if his actions are many-sided, we should accept the best." Source: St. Francis de Sales, Introduction to the Devout Life, Random House, Inc., 2002.
"To pass judgment on another is to usurp shamelessly a prerogative of God, and to condemn is to ruin one’s soul." Source: St. John Climacus, The Ladder of Divine Ascent
"I have rebuked people who were engaged in slander, and, in self-defense, these evildoers claimed to be acting out of love and concern for the victim of their slander. My answer to that was to say: 'Then stop that kind of love, or else you will be making a liar out of him who declared, [...]