Do not judge so that you will not be judged.  For by the standard you judge you will be judged, and the measure you use will be the measure you receive.  Why do you see the speck in your brother’s eye, but fail to see the beam of wood in your own?  Or how can you say to your brother, ‘Let me remove the speck from your eye,’ while there is a beam in your own?  You hypocrite! First remove the beam from your own eye, and then you can see clearly to remove the speck from your brother’s eye.

– Matthew 7:1-5

Do not judge.  I think he meant it literally.  Until you’re perfect, you’re incapable of accurate judgement.  And I imagine that once you’re perfect, judgement will hold no meaning.