Reference for Nedarim 69:4

בעא מיניה רבא מרב נחמן יש מעילה בקונמות או לא

— He replied, We have learnt this: WHERE PAYMENT IS TAKEN FOR THIS, THE BENEFIT MUST ACCRUE TO HEKDESH. This teaches that it is as hekdesh: just as the law of trespass applies to hekdesh, so it applies to Konamoth. This is dependent on Tannaim: If one Says, 'Konam, this loaf is hekdesh,'<span class="x" onmousemove="('comment',' Not specifying to whom, and therefore applying it to all, including himself. [Read with MS.M.: 'This loaf is hekdesh', omitting konam, v. also Shebu. 22a.] ');">⁷</span>

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