Reference for Pesachim 154:9

אפילו תימא רבי יהושע אלא קסבר רבי יהושע הציץ מרצה על העולין

[Even] a law which can be inferred a minori, the Writ takes the trouble of writing it. And R'Joshua? - Wherever we can interpret, we do interpret.<span class="x" onmousemove="('comment',' The principle that Scripture writes explicitly what can be inferred a minori holds good only when the verse cannot be employed for any other purpose.');">¹¹</span>

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