Reference for Zevachim 203:11

ומי אמר ר"ל הכי והכתיב (שמות ז, טו) ונצבת לקראתו על שפת היאור ואמר ר"ל מלך הוא והסביר לו פנים ורבי יוחנן אמר רשע הוא והעיז פניך בו איפוך

Why [add] 'and it says'?<span class="x" onmousemove="('comment',' Which implies that the first proof-text is insufficient.');">¹²</span> - You might argue that [the first proof-text] is written for [future] generations,<span class="x" onmousemove="('comment',' The first text deals with the status of the people then living, and for that reason Moses himself is not included. Thus it may not prove that he was a priest.');">¹³</span>

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