Reference for Menachot 151:15

הדיוט מהדיוט עדיף ליה

so [all meal-offerings] must consist of twelve cakes? - It is more reasonable to draw the inference from the cakes of the thank-offering for they<span class="x" onmousemove="('comment',' Sc. all other meal-offerings.');">¹⁷</span> [like the cakes of the thank-offering] are th offerings of ordinary persons, are freewill-offerings, are not offered by halves, are subject to the law of piggul, and may not be offered on the Sabbath or in uncleanness.<span class="x" onmousemove="('comment',' Whereas the griddle-cakes are the offering of the High Priest, brought as an obligation, and therefore override the Sabbath and uncleanness; they are offered half in the morning and half in the evening, and are not subject to the law of piggul (v. Glos.) .');">¹⁸</span>

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