Save "מקדש במלוה 
"
מקדש במלוה
Learn the גמ׳ אמר אביי
What part of the loan are you trying to be מקדש the אשה with? The actual money you had lent or the money she would have to pay you back?
Is the money you lent her still by her? Does is make a difference?
Learn the גמ׳ on דך מז
Learn רש״י there and learn רש״י here
start תוס׳
אָמַר אַבָּיֵי: הַמְקַדֵּשׁ בְּמִלְוֶה – אֵינָהּ מְקוּדֶּשֶׁת. בַּהֲנָאַת מִלְוֶה – מְקוּדֶּשֶׁת, וְאָסוּר לַעֲשׂוֹת כֵּן מִפְּנֵי הַעֲרָמַת רִבִּית. הַאי הֲנָאַת מִלְוֶה, הֵיכִי דָמֵי? אִילֵּימָא דְּאַזְקְפַהּ, דַּאֲמַר לַהּ אַרְבַּע בְּחַמְשָׁה – הָא רִבִּית מְעַלַּיְיתָא הוּא. וְעוֹד, הַיְינוּ מִלְוֶה! לָא צְרִיכָא, דְּאַרְוַוח לַהּ זִימְנָא.
§ Abaye says: With regard to one who betroths a woman with a loan, i.e., he previously lent this woman money and he now says that she is betrothed to him by means of that loan, she is not betrothed. The reason is that a woman can be betrothed only through her acceptance of money, or an item that has monetary value, at the time of the betrothal. Although this woman owes the man money, at the time the man states that she is betrothed to him, the loan is not in fact money but an obligation. Therefore, he does not actually give her anything at the time of the betrothal. By contrast, if he betroths her by means of the benefit of the loan, she is betrothed. But it is prohibited to do so, due to the fact that betrothing a woman via the benefit of a loan is an artifice used to circumvent the prohibition of receiving interest, as this enables the husband to gain an additional benefit from the loan. The Gemara clarifies: What is meant by this term: The benefit of the loan? If we say that it means that he established interest upon it when she took the loan, e.g., he said to her that he is lending her four coins in exchange for the repayment of five, and he betroths her by releasing her from the obligation to pay this additional coin, this is a case of full-fledged interest, not merely an artifice used to circumvent the prohibition of receiving interest. He is receiving full payment of the loan and an additional benefit. And furthermore, when he releases her from the obligation to pay this additional coin, he is simply forgoing another obligation she has toward him; he is not giving her anything. This is like a regular case of a betrothal with a loan, and therefore she should not be betrothed. The Gemara answers: No, it is necessary in a case where he extended the time of the loan for her. When the time for her to repay the loan arrived he extended the deadline and betrothed her with the financial benefit she receives from the extra time he is giving her to use the money. In this case he does betroth her with the value he is giving her at that time, but it is similar to interest, as it is included in the prohibition of interest to pay the creditor for an extension of the time of a loan.
אָמַר רַב: הַמְקַדֵּשׁ בְּמִלְוֶה – אֵינָהּ מְקוּדֶּשֶׁת, מִלְוָה לְהוֹצָאָה נִיתְּנָה. נֵימָא כְּתַנָּאֵי: הַמְקַדֵּשׁ בְּמִלְוֶה – אֵינָהּ מְקוּדֶּשֶׁת, וְיֵשׁ אוֹמְרִים: מְקוּדֶּשֶׁת. מַאי לָאו בְּהָא קָמִיפַּלְגִי, דְּמָר סָבַר מִלְוָה לְהוֹצָאָה נִיתְּנָה, וּמָר סָבַר מִלְוָה לָאו לְהוֹצָאָה נִיתְּנָה? וְתִסְבְּרָא?! אֵימָא סֵיפָא: וְשָׁוִים בְּמֶכֶר שֶׁזֶּה קָנָה. אִי אָמְרַתְּ מִלְוָה לְהוֹצָאָה נִיתְּנָה, בְּמַאי קָנֵי?! אָמַר רַב נַחְמָן: הוּנָא חַבְרִין מוֹקֵים לַהּ בְּמִילֵּי אוּחְרֵי, וְהָכָא בְּמַאי עָסְקִינַן — כְּגוֹן שֶׁאָמַר לַהּ: ״הִתְקַדְּשִׁי לִי בְּמָנֶה״ וְנִמְצָא מָנֶה חָסֵר דִּינָר. מָר סָבַר: כְּסִיפָא לַהּ מִילְּתָא לְמִיתְבְּעֵיהּ. וּמָר סָבַר: לָא כְּסִיפָא לַהּ מִילְּתָא לְמִיתְבְּעֵיהּ.
§ Rav says: With regard to one who betroths a woman with a loan, she is not betrothed, since a loan is given to be spent. Consequently, from the moment the money is lent it no longer belongs to the lender, and he cannot betroth a woman with it. The Gemara suggests: Let us say that this is subject to a dispute between tanna’im, as it was taught in a baraita: With regard to one who betroths a woman with a loan, she is not betrothed, and some say she is betrothed. What, is it not that they disagree with regard to this: One Sage holds that a loan is given to be spent, and one Sage holds that a loan is not given to be spent? The Gemara questions this suggestion: And how can you understand it that way? Say the latter clause of that same baraita: And they agree with regard to the case of a sale that he acquires it. Although they disagree as to whether one can betroth a woman with a loan he has given her, they agree that a lender can purchase an item from the debtor in exchange for forgiving the money he has lent him. If you say that a loan is given to be spent, with what has he acquired it? There is no money with which to effect an acquisition. No proof can be derived from this baraita, which cannot be understood as stated. Rav Naḥman says: Our colleague Rav Huna interprets the baraita as referring to other matters and not as referring to a straightforward case of a loan. And with what are we dealing here? A case where he said to her: Be betrothed to me with one hundred dinars, and it was found to be one hundred dinars less one dinar, the missing dinar is considered to be a loan that he has taken from her. One Sage, who said the woman is not betrothed, holds that the matter is embarrassing for her, preventing her from claiming the final dinar from him, and since he has failed to fulfill his statement she is not betrothed. And one Sage, who said that she is betrothed, holds that the matter is not embarrassing for her and is not preventing her from claiming the final dinar. He is therefore considered to have fulfilled his statement and borrowed one dinar from her, which he will repay in due course, but she is nevertheless betrothed.