Reference for Keritot 48:22

אשם תלוי בנדבה אתי דתנן ר"א אומר

he who taught the one clause cannot have taught the other.<span class="x" onmousemove="('comment',' I.e., the Mishnah is self-contradictory in combining two views which are at variance with one another. The views, however, are derived from different Schools.');">¹⁴</span>

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