In the Talmud in Shavuot [page 44a]
The question is that the Gemara concludes like Rav Joseph and that is how the Rambam decides. The question is what does the Rambam do with the Gemara in Bava Metzia in which Rav Nachman says about a משכון [collateral for a loan] that even though one can use it he is not liable in אונסים [armed robbers].
I also wanted to point out why the Rif in our Gemara in Shavuot says the law straightforwards that the lender that loses the pledge is like a שומר שכר paid guard, and in a case of armed robbers, he loses only the amount of the collateral not the whole loan. The reason is quite elegant. It comes out of the steady progression of the Gemara itself to reach that point.
The Mishna says in an argument about a case when the pledge was lost that the lender loses only the amount the pledge was worth. Shmuel said he loses the whole loan. [he was talking about when the borrower said so openly.] R Eliezer says the lender does not lose anything and R Akiva says he loses the loan. If the pledge is worth the entire amount then why would R Eliezer disagree? So everyone disagrees with Shmuel. Their argument is about R. Isaac that the lender owns the pledge. But if it was taken not at the time of the loan everyone agrees with R Isaac. So it is at the time of the loan and the disagreement is if a guard of a lost object is considered to be paid or not. But that is only if he needs to pledge. If you follow the logic of the Gemara here you can see why the Rif (Isaac Alfasi) says that nothing matters the lender that loses the pledge loses only the amount it was worth. I can't go into it this minute but by following the logic of the Talmud you can see how he was led to this conclusion step by step.
The key is to remember that if we don't hold by Shmuel then it does not matter if the borrower said it is against the loan or not. And if it is at the time of the loan of not also makes no difference since we go by R Akiva against R Eliezer. And even if the lender needs the pledge we still consider he is doing a mitzvah and so gets the coin of Rav Joseph and so is a שומר שכר
There is one question I have even though I have not even gotten to learn Tosphot properly yet. The Rif does as I say take all the divisions and throws them out, and most of this you can see in the Gemara itself. The last division though I find difficult. If they all hold by R. Isaac that the pledge is owned when it was taken not at the time of the loan, and their argument is at the time of the loan and it goes by the debate between Raba and Rav Joseph, then there is a difference! A pledge taken not at the time of the loan is owned, and for a pledge taken at the time of the loan, the lender is only a שומר שכר [paid guard]. So why does the Rif say for a pledge taken even not at the time of the loan he is a שומר שכר. He should say if taken not at time of loan he owns it and if taken at time of loan he is a paid guard.
From what I can tell Rashi answers this question in Bava Metzia. [That is he explains the Gemara there in a way that can help us understand the Rif in Shavuot--that is we can say perhaps the Rif was learning like Rashi.] He says on pg 84 that the pledge is owned completely only until the loan is paid. He says openly that what Rabbi Isaac means is that the lender is not a paid nor unpaid guard. He is an owner. But the ownership only exists until the second the borrower comes to pay back the loan. So this is not what I wrote in my ideas in Bava Metzia and I am sad to say I have to go back and correct my mistake. I was thinking around page that the lender owns the object completely.
Does this help us? Maybe. But still it looks like we still end up that for the pledge taken not at the time of the loan he is more than a paid guard--he owns it and thus is liable even in a case it was stolen by force. That is a case the paid guard would not have to pay for. So we still are in a mess concerning the Rif.
That is to him when the pledge was taken not at the time of the loan the lender is a paid guard. This seems not like Rabbi Isaac. The only thing I can think might help is the Gemara in Bava Metzia 104 about דורשין לשון הדיוט that is he would own it but the language of the document brings him down one notch. Because in Shavuot 43b the whole argument of R Akiva and R Eliezer does not apply to when there is a document. That is because everyone agrees then he is a paid guard.
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שבועות מ''ד ע''א
The question is that the גמרא concludes like רב יוסף and that is how the רמב''ם decides. The question is what does the רמב''ם do with the גמרא in בבא מציעא in which רב נחמן says about a משכון that even though one can use it he is not liable in אונסים.
I also wanted to point out why the רי''ף in our גמרא in שבועות says the law that the lender that loses the משכון is like a שומר שכר paid guard, and in a case of armed robbers, he loses only the amount of the משכון, not the whole loan. The reason is quite elegant. It comes out of the steady progression of the גמרא itself to reach that point.
The משנה says in an argument about a case when the משכון was lost that the מלווה loses only the amount the משכון was worth. שמואל said he loses the whole loan. He was talking about when the לווה said so openly. רבי אליעזר says the מלווה does not lose anything and רבי עקיבא says he loses the loan. If the משכון is worth the entire amount, then why would רבי אליעזר disagree? So everyone disagrees with שמואל. Their argument is about רבי יצחק that the מלווה owns the משכון. But if it was taken not at the time of the loan everyone agrees with רבי יצחק. So it is at the time of the loan and the disagreement is if a שומר of a lost object is considered to be paid or not. But that is only if he needs to משכון. If you follow the logic of the גמרא here you can see why the רי''ף says that nothing matters the מלווה that loses the משכון loses only the amount it was worth.
The key is to remember that if we don't hold by שמואל then it does not matter if the borrower פירש it is against the הלוואה or not. And if it is at the time of the הלוואה or not also makes no difference since we go by רבי עקיבא against רבי אליעזר. And even if the מלווה needs the pledge we still consider he is doing a מצווה and so gets the פרוטה of רב יוסף and so is a שומר שכר
The רי''ף does as I say take all the divisions and throws them out, and most of this you can see in the גמרא itself. The last division though I find difficult. If they all hold by רבי יצחק that the משכון is owned when it was taken not at the time of the הלוואה, and their argument is at the time of the loan and it goes by the debate between רבה and רב יוסף, then there is a difference! A משכון taken not at the time of the loan is owned, and for a משכון taken at the time of the הלוואה, the מלווה is only a שומר שכר . So why does the רי''ף say for a משכון taken even not at the time of the loan he is a שומר שכר. He should say if taken not at time of הלוואה he owns it, and if taken at time of loan he is a שומר שכר.
Maybe רש''י answers this question in בבא מציעא. That is he explains the גמרא there in a way that can help us understand the רי''ף in שבועות. That is we can say perhaps the רי''ף was learning like רש''י. He says on דף 84 that the משכון is owned completely only until the הלוואה is paid. He says openly that what רבי יצחק means is that the מלווה is not a שומר שכר nor שומר חינם. He is an owner. But the ownership only exists until the second the לווה comes to pay back the הלוואה.
Does this help us? Maybe. But still it looks like we still end up that for the משכון taken not at the time of the loan he is more than a שומר שכר. He owns it and thus is liable even in a case it was stolen by force. That is a case the שומר שכר would not have to pay for. So we still are in a mess concerning the רי''ף.
That is to him when the משכון was taken not at the time of the loan the lender is a paid guard. This seems not like רבי יצחק. The only thing I can think might help is the גמרא in בבא מציעא ק''ד about דורשין לשון הדיוט that is he would own it but the language of the document brings him down one notch. Because in שבועות מג ע''ב the whole argument of רבי עקיבא and רבי אליעזר does not apply to when there is a document. That is because everyone agrees then he is a paid guard.
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כלומר להרי''ף כאשר המשכון נלקח לא בזמן של ההלוואה המלווה הוא שומר שכר. זה נראה לא כמו רבי יצחק. הדבר היחיד שאני יכול לחשוב עשוי לעזור הוא הגמרא בבא מציעא ק''ד על דורשין לשון ההדיוט שהוא היה בבעלותו, אבל השפה של המסמך מורידה אותו החריץ אחד. כי בשבועות מ''ג ע''ב כל הטיעון של הרבי עקיבא ורבי אליעזר אינו חל על כאשר יש מסמך. זאת משום שכולם מסכים שאז הוא שומר שכר.
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English
What I wanted to add is this. In Bava Metzia page 104 we have this idea of דורשין לשון הדיוט. What does that mean there? The Gemara there understands this to mean we can't take a pledge that has a larger value than the loan itself. Why not? It seems to me the reason is we take the pledge out of the category of being a pledge to being bought. But that does not seem to fit the Gemara in Shavuot in which the pledge if taken not at the time of loan is automatically bought and owned. It is rather the pledge taken at the time of the loan that Rabbi Eliezer and Rabbi Akiva disagree about and we go by Rabbi Akiva that he is considered a paid guard. And the Rif says in all cases he is a paid guard. So דורשין לשון הדיוט seems to be ambiguous. You could say it means we take even the loan taken at the time of the loan and consider it owned and not just as a pledge. I mean that even Rabbi Akiva and Rabbi Eliezer would agree that because of דורשין that it too would be considered bought and owned until the lender pays back the loan. The other way to understand this is to say that דורשין לשון הדיוט tells us to take what was a normal pledge which is already considered bought and owned and make it into a pledge that the lender is just a paid guard for. This last way fits the Rif in Shavuot. But it does not fit the Gemara in Bava Metzia
English and Hebrew
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What I wanted to add is this. In בבא מציעא דף ק''ד we have this idea of דורשין לשון הדיוט. What does that mean there? The גמרא there understands this to mean we can't take a משכון that has a larger value than the הלוואה itself. Why not? It seems to me the reason is we take the משכון out of the category of being a משכון to being bought. But that does not seem to fit the גמרא in שבועות in which the משכון if taken not at the time of הלוואה is automatically bought and owned. It is rather the משכון taken at the time of the הלוואה that רבי אליעזר and רבי עקיבא disagree about and we go by רבי עקיבא that he is considered a שומר שכר. And the רי''ף says in all cases he is a שומר שכר. So דורשין לשון הדיוט seems to be ambiguous. You could say it means we take even the הלוואה taken at the time of the הלוואה and consider it owned and not just as a משכון. I mean that even רבי עקיבא and רבי אליעזר would agree that because of דורשין that it too would be considered bought and owned until the לווה pays back the חוב. The other way to understand this is to say that דורשין לשון הדיוט tells us to take what was a normal משכון which is already considered bought and owned and make it into a משכון that the מלווה is just a שומר שכר for. This last way fits the רי''ף in שבועות. But it does not fit the גמרא in בבא מציעא