We have a tradition attributed to the Baal Shem Tov: When one hears an uncomplimentary report about another Jew - even if he does not know the individual referred to - he should be very deeply pained. For one of these two is certainly in the wrong: If what is being said about the individual is true, then the person being spoken about is defective; and if it is not true, then the talebearer is the one in an unhealthy situation.

HaYom Yom, entry for 12 Kislev