St Seraphim of Sarov

One must not judge anyone, although with one’s own eyes one may see someone sin or wallow in transgression of the commandments of God; according to the word of God: “Judge not, that ye be not judged” (Mat. 7:1). One must not nourish in the heart evil or hatred towards one’s neighbor who is hostile. Rather, one must love him, and as much as one is able, do him good, following the teachings of our Lord Jesus Christ: “Love your enemies, do good to them that hate you” (Matt. 5:44). And so, if we would strive as much as we are able to fulfill all this, then we can have the hope that in our hearts shall shine the Divine light, revealing to us the way to the Jerusalem above.

Why do we judge our brethren? Because we do not strive to know ourselves. Whoever occupies himself with self-knowledge never notices others; judge yourself, and you will stop judging others. And so, beloved, let us not observe the sins of others and judge them, so as not to hear: “The sons of men, their teeth are weapons and arrows, and their tongue is a sharp sword” (Ps. 56:5). For when the Lord leaves a man to himself, then the devil gets ready to crush him, as a millstone does a grain of wheat.