Reference for Moed Katan 51:7

שאול זה נשיא יהונתן זה אב ב"ד על עם ה' ועל בית ישראל אלו שמועות הרעות

Now 'Saul', that is the Nasi [Prince]; 'Jonathan', that is the Ab Beth din.' And for the people of the Lord and for the house of Israel', tha refers to 'evil tidings' [that reached them]. Said Rab B'Shabba to R'Kahana: Might not one explain that [they did] not [rend their clothes] until [after hearing] all those misfortunes [that had then happened]?<span class="x" onmousemove="('comment',' The case of Saul and Jonathan.');">⁷</span>

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