Reference for Eruvin 108:23

אמר רב חסדא אין תורה נקנית אלא בסימנין שנאמר שימה בפיהם אל תקרי שימה אלא סימנה

may be said to agree even with the view of the Rabbis, since Aaron's trouble had to be taken into consideration.<span class="x" onmousemove="('comment',' As he had to sit on the left of Moses when the two were alone, he was allowed to remain in the same position, even after the others had entered, in order to save him the trouble of moving from one place to another.');">⁴⁹</span> R'Pereda had a pupil whom he taught his lesson four hundred times before the latter could master it. On a certain day having been requested to attend to a religious matter he taught him as usual but the pupil could not master the subject.' What', the Master asked: 'is the matter<span class="x" onmousemove="('comment',' Lit., 'what is the difference'.');">⁵⁰</span>

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