Leviticus 19:15 ..... but in righteousness shalt thou judge thy neighbour.
In Samuel 16:7 ..... for the Lord seeth not as man seeth; for man looketh on the outward appearance, but the Lord looketh on the heart.
Matt 7:1-2 Judge not, that ye be not judged. For with what judgment ye judge, ye shall be judged: and with what measure ye mete, it shall be measured to you again.
Matt 7:24 Judge not according to the appearance, but judge righteous judgment.
John 8:7 So when they continued asking him, he lifted up himself, and said unto them, He that is without sin among you, let him first cast a stone at her.
The subject of judgment of one another is perhaps the most confused issue in the scriptures. Under the Mosaic Law, judgment of one's neighbor was prescribed, with a significant number of capital offenses , some of which seem ruthlessly draconian. The admonition to judge righteously might appear straightforward to some, but we are surrounded by evidence of flawed human judgment.
In the midst of all the OT law keeping practices we encounter the story of David's selection as king in I Samuel 16:7. God enjoins judgment which looks on the heart. How does anyone look on another man's heart? We might blithely assume that we can look on the heart by observing outward things like words and deeds, but the assumption is based on the very outward things God dismissed. Must we believe that God cautioned simply against judging based on personal appearance but not other highly subjective external observations. I would conclude that only God looks on the heart and therefore is the only one capable of judging righteously.
Then later, we encounter the words of Jesus. Within the very same chapter Jesus condemns judgment and turns around and prescribes "righteous" judgment. Then in the account of the woman taken in adultery, Jesus rejects her stoning by suggesting that only the sinless could execute judgment. Some want to condemn this story as a fabrication, but it remains a longstanding part of the very book the church insists is infallible, inerrant, and fully the very word of God.
All those who claim to be the God appointed judges of righteous in others, by citing the Bible, stand on shaky ground in my mind. Exactly how does righteous judgment of others occurs without godlike omniscience? My suggestion would be that we can righteously assess our own lives and conduct, but we cannot do the same for another until we walk many a mile in their shoes and then perhaps get a slight glimpse into their heart.
The movie, Manchester by the Sea, is a great example in how we as humans can easily misjudge another. Lee Chandler, the main character, is seemingly a very strange and unpleasant man. His demeanor is sullen, foul mouthed, and violence prone. As the story develops, the viewers learn of a personal tragedy which has doomed Chandler to endless bouts of unimaginable grief and guilt. This tragedy haunts him, and his despair drives his anti-social behaviors, which are a form of self abasement and penance. A snap judgment about this man's heart, based on behavior, would be woefully off base. That is potentially true, if not inevitably true, of every human judgment of another.