Giving tochacha is an obligation every Jew has to give to every Jewish brother when he’s sinning. Halachicly. Required. The only exception, according to halacha, is if you know with certainty it will not work and it will backfire. If there’s even a slight chance it might be helpful it is halachicly obligatory to reprimand. Privately and sweetly at first and publicly if the private admonition failed. That is Hashem’s rule.
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