Reference for Bava Batra 347:6

אמר ר' יצחק לשון ערבות ערבות לשון קבלנות קבלנות

R. Huna said: [Should one say], 'Lend him [a sum of money] and I [shall be] guarantor'. 'Lend him and I [shall] repay [you]', 'Lend him and I [shall be] liable [for the loan]', [or] 'Lend him and I [shall] give [it back to you]' — all these are expressions of guarantee.<span class="x" onmousemove="('comment',' [H], security. Since the expression of lending was used the guarantor has thereby intimated that the other shall be the borrower. He has consequently to pay only in the case where the debtor has no property of his own. ');">⁶</span>

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