Passing judgment on others is aways a sign that one has not yet encountered oneself. Hence pious individuals who become incensed over others have not yet encountered their own truth. Their piety has not yet confronted them with themselves and their own sin. For as Father Moses says: "If anyone is bearing his sins, he does not look on those of his neighbors."
Judging gives us no rest. For even while we are condemning the other, we unconsciouly sense that we too are not perfect. Thus, renouncing judgment and condemnation is a way to inner peace with ourselves. We let others be as we are, and in this way we can also be ourselves.
...Not-judging comes out of the encounter with the self. Those who have encountered themselves know all about their own errors. They know their shadow side. They know that they bear within themselves what they condemn in others... Psychologists tell us that when we pour abuse on others we are revealing what is in ourselves. We project our own shadow side, our repressed wishes and needs, onto others; and so we revile them instead of looking our own truth in the eye.