Reference for Moed Katan 51:9

ומי קרעינן אשמועות הרעות והא אמרו ליה לשמואל קטל שבור מלכא תריסר אלפי יהודאי במזיגת קסרי ולא קרע לא אמרו אלא ברוב צבור וכמעשה שהיה

he did not [then] rend his clothes? - They [the Sages] did not say [it should be done] save where the misfortune involves the larger part of the Community resembling the typical instance.<span class="x" onmousemove="('comment',' Of Saul and Jonathan.');">⁹</span> And is it a fact that King Shapur slew Jews? For [it is reported] that King Shapur said to Samuel,<span class="x" onmousemove="('comment',' They were on very friendly terms.');">¹⁰</span>

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