Reference for Bava Metzia 129:12

אמר רב פפא טרשא דידי שרי מאי טעמא שכראי לא פסיד זוזי לא צריכנא אנא הוא דקא עבידנא מילתא גבי לוקח

<b><i>GEMARA</i></b>. What is the difference between the first clause and the second? — Rabbah and R. Joseph both said: Rent is payable at the end [of the year]; hence, since it is not yet time to claim, it is not payment for waiting,<span class="x" onmousemove="('comment',' I.e., the higher price for the monthly arrangement cannot be regarded as such, since the money is not yet due. ');">⁸</span>

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