Reference for Eruvin 71:10

לא תימא ספק מבעוד יום נתקנו אלא אימא ספק מבעוד יום נדמעו ספק משחשיכה נדמעו

- in any such case<span class="x" onmousemove="('comment',' Lit., 'this'.');">²²</span> the 'erub is not [deemed to be one whose validity is in] doubt [and which is consequently] effective.<span class="x" onmousemove="('comment',' Tosef. 'Er. II.');">²⁶</span> Wherein, however, does terumah<span class="x" onmousemove="('comment',' In the first clause where R. Jose rules the 'erub to be effective if it is doubtful whether it contracted uncleanness or was prepared for use before or after twilight.');">²⁷</span>

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