Reference for Bekhorot 52:39

מסתברא

- Scripture refers you to the Sages [for the precise interpretation].<span class="x" onmousemove="('comment',' Scripture does not state sixty days, but the Sages explain that fifty days are required, basing this on a comparison between the text 'The fullness of thy harvest' and the verse 'Likewise thou shalt do with thy oxen'.');">²³</span>

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