Reference for Taanit 59:11

אבל קורא הוא במקום שאינו רגיל לקרות ושונה במקום שאינו רגיל לשנות וקורא בקינות באיוב ובדברים הרעים שבירמיה ותינוקות של בית רבן בטלין משום שנאמר (תהלים יט, ט) פקודי ה' ישרים משמחי לב

Eating, drinking, bathing, anointing, the wearing of shoes and marital relations are forbidden thereon. It is also forbidden [thereon] to read the Law, the Prophets, and the Hagiographa or to study Mishnah, Talmud, Midrash, Halachoth, or Aggadoth;<span class="x" onmousemove="('comment',' The study of all these brings delight to the genuine student.');">⁹</span> he may, however, read such parts of Scripture which he does not usually read and study such parts of Mishnah which he usually does not study;<span class="x" onmousemove="('comment',' The study of new subjects needs great application and the pleasure derived from the study is eclipsed by the efforts expended.');">¹⁰</span>

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