Reference for Bava Batra 346:4

מתקיף לה רב נחמן האי דינא דפרסאי

— Both Rabbah and R. Joseph explain: [Because the guarantor can say,] 'You have entrusted me with a man;<span class="x" onmousemove="('comment',' The debtor; i.e., the creditor has, so to speak, put the debtor in charge of the guarantor who has undertaken to present him when payment falls due. ');">⁷</span> and a man have I handed over to you'.<span class="x" onmousemove="('comment',' Since the debtor neither died nor absconded, the guarantor has carried out his obligation. As the debtor is present in person the claim is to be addressed to him and not to the guarantor. ');">⁸</span>

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