"He who rebukes a man will in the end gain more favor than he who has a flattering tongue." Proverbs 28:23 (NIV)
We live in such a society that screams "Do not judge!" Because of complancent attitude, we allow sin to run rampant in one another. We can't judge them, so they can do whatever they want, believing that they receive God's blessings when, in reality, they're on a path of self-destruction.
The Bible never says "do not judge." It says that we cannot judge another person to Hell and damnation. That's the Lord's job and He will do it without you or me.
We ARE to judge, though. We are to judge sin for what it is. Read 1 Corinthians. If I see my neighbor stumbling and I do not warn him or her of the consequences, I am doing my neighbor a grave wrong. He doesn't need a flattering tongue but rather a truthful word that could save him from Hell.
Let me repeat, it is NOT my job to condemn to Hell. God will do that and I am very wrong if I even try to judge a PERSON. But, to ignore dangerous warning signs in a person's life and never tell him the Good News of Jesus' forgiveness and the victory over sin He alone can provide is a terrible thing to do. I should love my fellow man enough to tell him the truth if I believe that it is the truth.
If I don't judge between right and wrong, how can I do what is right? To judge simply means to discern, to decide whether something is right or wrong.