Reference for Eruvin 69:13

ר' יוסי ור"ש אומרים ספק עירוב כשר אמר ר' יוסי אבטולמוס העיד משום חמשה זקנים על ספק עירוב שכשר:

to be explained?<span class="x" onmousemove="('comment',' If the cupboard was big, all would agree that it is subject to the law of 'tent'; how then could the first Tanna maintain that the 'erub is effective? If, however, it was a small one, of a capacity of less than forty se'ah of liquids, all would agree that it has the status of a 'vessel'; how then could R. Eliezer maintain that the 'erub is ineffective?');">⁴³</span> - Both Abaye and Raba replied: We are dealing with a lock that<span class="x" onmousemove="('comment',' So MS.M. Cur. edd., 'and'.');">⁴⁴</span> was tied with a cord for the cutting of which a knife is required.<span class="x" onmousemove="('comment',' It being too strong to be broken by the bare hands. Had this been possible even R. Eliezer would have permitted the breaking if the cord (cf. Bezah 31b) ; and, since the cupboard could be opened, the 'erub which would in consequence be accessible, would be effective. Though the breaking of a cord on the Sabbath was permitted in connection with 'vessels' only, and not with structures (such as a tent or a cupboard) that are fixed to the ground, the 'erub here would nevertheless be effective because at the twilight of Friday when the 'erub comes into force, the breaking of the cord, which on the Sabbath itself is forbidden as a Rabbinical measure only, is not even Rabbinically forbidden.');">⁴⁵</span> The first Tanna holds the same view as R'Jose who laid down: All instruments may be moved on the Sabbath except a large saw<span class="x" onmousemove="('comment',' Used for the cutting of wood.');">⁴⁶</span>

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