[Soncino translation]
Avos (4:4) R. JOHANAN B. BEROKAH24 SAID: WHOEVER PROFANES THE NAME OF HEAVEN25 IN SECRET,26 THEY27 EXACT THE PENALTY FROM HIM IN THE OPEN.28 [IN THIS RESPECT, IT IS ALL] ONE [WHETHER ONE HAS ACTED] IN ERROR, AND [IT IS ALL] ONE29 [WHETHER ONE HAS ACTED] WITH PRESUMPTION, IN [A CASE WHERE THE RESULT IS] THE PROFANATION OF THE NAME.30
Notes:
(26) How can any secret misdeed be a profanation of the Name, which necessarily implies a knowledge of the sin by at least one other than the guilty person? Tosaf. Yom Tob says: When the sin can be committed only together with another person, e.g. prohibited sexual intercourse. L.: There are two kinds of ‘profaners of the Name’: (a) one who commits a sin, making it clear to others that he contemptuously disregards the divine commandments; (b) one who transgresses secretly. not because he is concerned for the Glory of the Name of God, but for his own reputation among his fellow men, by whom he wishes to be regarded as a pious man. The latter is profaning the Name in secret, and it is this duplicity that is to be exposed by punishment in public. V.: A sin committed in secret which, should it become known, would cause a profanation of the Name.
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Yoma(86b): One should expose the hypocrites to prevent chillul HaShem as it says in Yechezkeil (3:20):When a righteous man turns from his righteousness and he commits sin, I will lay a stumbling block before him.
Rashi(Yoma 86b): Publicize the hypocrites – These people are wicked but they represent themselves as righteous. Therefore if someone is aware of their deeds – it is a mitzva to publicize them because of chillul HaShem. That is because people learn from their deeds since they think they are tzadikim. Furthermore when they are punished from Heaven, people says “what benefit is merit to protect against suffering.”
Chofetz Chaim(Lashon Harah 4:7): All these laws which I have written apply specifically to those whose conduct and manner is to have regret for his sins. However if you investigate his path and discover that he has no fear of G‑d and he is continually doing things which are not good such as throwing off the yoke of heaven or that he doesn’t avoid doing even a single transgression which everybody clearly knows is prohibited – whether it is the sin that you want to reveal and has done it a number of times on purpose or he has done some other transgressions a number of times which is clear to all that it is prohibited – this clearly shows that he is not transgressing because his lust overcame him but rather that it doesn’t bother him that he is transgressing and he has no fear of G‑d. Therefore it is permitted to degrade him and to describe his shame either before him or not before him. Therefore if he does some deed or says something and there is a question of whether to judge it favorably or unfavorably – it is necessary to judge him unfavorably since he has established himself as completely wicked (rasha) in other matters. Similarly our Sages say that the mitzva of “Do not distress others” only applies to those who are equal to you in keeping Torah and mitzvos. Therefore someone who has no concern for the word of G‑d, it is permitted to shame him and to inform others of his abominations and to heap scorn on him until he repents. This is what the Rambam (Hilchos De’os 6:8) said. Nevertheless you should be careful not to forget the conditions that apply in this case (Be’er Mayim Chaim Lashon Harah 4:32).
