Reference for Pesachim 109:1

תנא קולי קולי קתני:

The Tanna teaches a series of leniences.<span class="x" onmousemove="('comment',' The whole series of 'there is no difference' etc. is taught by the same Tanna, and in each he merely wishes to intimate a point of leniency. Thus he first teaches that the Ninth of Ab is not more lenient than the Day of Atonement save that the doubt of the former is permitted. Then he states that the Ninth');">¹</span> AND IN ALL PLACES SCHOLARS etc. Shall we say that R'Simeon B'Gamaliel holds that we do not fear [the appearance of] conceit, while the Rabbis hold that we do fear [the appearance of] conceit?

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