And You open the book of recollections, and it reads on its own, and the seal of each person's hand is therein (Machzor of Rosh Hashanah).

The Baal Shem Tov taught that a person must be extremely cautious not to pass harsh judgment on others. "It is yourself that you are judging," said the Baal Shem Tov.

When the prophet, Nathan, rebuked King David following the Bath-Sheba incident, he related the parable of a wealthy man who owned abundant livestock, and who robbed a poor neighbor of his one and only lamb. David was outraged at this terrible injustice, and in his anger exclaimed, "I swear by God, that man is deserving of death!" Nathan then said, "You are that man!" (II Samuel 12:1-5).

God knows that personal interest makes us oblivious to the significance of our own misdeeds, so He contrives to make us observe in others actions and behavior similar to our own. How we react to our own acts as we see them in others determines how God will judge us. If we are considerate and lenient in our judgment, and give others the benefit of doubt, allowing them the broadest latitude of circumstances that might have caused them to behave improperly, th will judge us with equal leniency. But if we are self-righteous and quick to condemn others, we will be judged with equal severity.

On the Days of Judgment, the books of our deeds are opened, and they "had on their own"; i.e. our actions speak for themselves. "And the seal of each person's hand is therein"; i.e. we have rendered our own judgment on our actions by the way we reacted to similar actions when we observed them in others. God merely carries out the judgments we have made on ourselves.