Reference for Bava Batra 328:15

בשלמא התם איכא לשון הרע אלא הכא מאי לשון הרע איכא משום דרב דימי דתני רב דימי אחוה דרב ספרא לעולם אל יספר אדם בטובתו של חבירו שמתוך טובתו בא לידי רעתו

'How correct is this writing'? said Rabbi. 'I did not write it', replied the other, 'Judah Hayyata wrote it'. 'Keep away from tale-bearing'. [Rabbi] called to him. In the first case<span class="x" onmousemove="('comment',' Lit., 'there', in the case of the deed which incurred Rabbi's displeasure. ');">⁴⁹</span> one can well understand [Rabbi's exhortation, since] there was slander; what tale-bearing, however, was there here?<span class="x" onmousemove="('comment',' In connection with the Book of Psalms which elicited Rabbi's praise. ');">⁵⁰</span> — Owing to [the teaching] of R. Dimi; for R. Dimi, brother of R. Safra, taught: A man should never speak in praise<span class="x" onmousemove="('comment',' Lit., 'good'. ');">⁵¹</span> of his friend, because by praise of him he brings about<span class="x" onmousemove="('comment',' Lit., 'he comes'. ');">⁵²</span>

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