Reference for Taanit 57:7

וכתיב (במדבר יד, א) ותשא כל העדה ויתנו את קולם ויבכו העם בלילה ההוא אמר רבה אמר ר' יוחנן (אותו היום ערב) תשעה באב היה אמר להם הקב"ה אתם בכיתם בכיה של חנם ואני קובע לכם בכיה לדורות

- Abaye replied: Tammuz of that year was a full month [of thirty days],<span class="x" onmousemove="('comment',' The additional day brings the figure up to forty. sgun');">¹¹</span> for it is written, He hath called a solemn assembly against me to crush my young men.<span class="x" onmousemove="('comment',' Lam. I, 15. The word 'an appointed season', festival, is interpreted homiletically as a season appointed for mourning, as the Talmud goes on explaining.');">¹²</span> And it is further written, And all the congregation lifted up their voice, and cried; and the people wept that night.<span class="x" onmousemove="('comment',' Num. XIV, 1.');">¹³</span>

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