Reference for Shabbat 47:4

שני וחמישי מאי עבידתייהו אלא שני וה' וב' של תעניות ומעמדות ערבית ושחרית ומנחה מתפלל שמונה עשרה ואומר מעין המאורע בשומע תפלה ואם לא אמר אין מחזירין אותו (ואין בהן קדושה על הכוס) ואין בהן הזכרה בברכת המזון:

and if one does not insert it, he is turned back;<span class="x" onmousemove="('comment',' To repeat the passage, because these are special occasions instituted in the Bible. ');">¹²</span> and there is no Sanctification over wine,<span class="x" onmousemove="('comment',' Lit., 'goblet'. V. p. 102, n. 8. ');">¹³</span> and mention thereof is made in grace after meals. On those days when there is no additional offering, viz., Mondays, Thursdays,<span class="x" onmousemove="('comment',' On these days Reading of the Law forms part of the Service, as on the Sabbath. According to the Talmud (B.K. 82a) this was instituted by Ezra, so that three days should not pass without Torah. ');">¹⁴</span> Fasts,<span class="x" onmousemove="('comment',' Specially proclaimed for rain (Ta'an. 10a). ');">¹⁵</span>

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