Following up on this question: does the rule “one who betroths with a loan, she is not betrothed” apply to a loan before its due date arrives? Or also after? And if also after, does that include a case where the borrower has money? Or only a case where she has no money to return at the moment? And how does this fit with the Gemara in Bava Metzia 4a: “These coins, which he admits are included, are regarded as though the lender has already taken them,” implying that the very admission regarding the loan creates a status of “here it is,” in which the lender is considered as though he has already received his money. If so, why should he not be able to betroth with them (after the due date)?

As far as I know, it applies even afterward, and even when the borrower has money.
The discussion in Bava Metzia is only about admission together with “here it is,” where it is then really by the lender, and the remaining dispute is only about the rest, so it is not a case of partial admission that obligates an oath. Mere admission is not “here it is,” for otherwise the Torah would never have had an oath for one who partially admits. So from there there is actually proof for my claim: with mere admission, the money is still the borrower’s.

Rashi explains there: “And ‘here it is’—I did not spend them, and they are yours wherever they are,” which implies a situation where the money is still with the borrower and has not yet actually been returned to the lender. As for mere admission, it seems to me one should distinguish between a case where the borrower has money/land, so that from the moment of admission they pass into the lender’s possession, and therefore this is “here it is” and he is exempt from the oath of partial admission (and perhaps one could also betroth with them), and a case where the borrower currently has no money/land to return, in which case he is obligated in the oath of partial admission.

Rashi’s view is that even such a case is “here it is.” Other medieval authorities disagree. In any case, he says, “and they are yours wherever they are,” so in any event this is not just a plain admission. A plain admission is certainly not enough, and the proof is that there is an oath for partial admission.
But Rashi here is not speaking about a case where the borrower just has money; rather, he has the original coins and says that they belong to the lender wherever they are. Ordinary money that he has does not become the lender’s through admission.

But then anyone could exempt himself from the oath of partial admission—he would simply claim that he has the original coins (all coins are alike). And even if he does not claim that, one could exempt him from the oath by a “since” argument: since he could have claimed that they were the original coins (according to the opinion that such a “since” argument can exempt from an oath).

In any case, the one who admits has a “since” argument to admit with “here it is.” It may be that the “since” does not exempt, because “here it is” is not a valid “since,” since if he says “here it is” he immediately loses the money.
Beyond that, if the Torah obligates an oath for every partial admission, then this itself teaches that the “since” argument does not exempt. Like Rabbi Chiya’s first teaching, which explains that the “since” argument that he could have denied everything does not exempt from the oath.

The “since” argument I meant was someone who partially admits and claims “here it is” regarding coins that are not the original ones, so that he should be exempt from the oath because he could have claimed that the coins were the original ones. And even if we give up the “since” here, why should we require that the coins specifically be the original coins? After all, that cannot be verified, and if someone wants to exempt himself from the oath through “here it is” with non-original coins, he can easily lie and we would not be able to check it.

Someone who claims “here it is” regarding non-original coins is still exempt from the oath. What Rashi claims is that with the original coins, one need not actually hand over the money; it is enough to say that it is his wherever it is. Perhaps he sees a difference: with the original coins, if you have not yet spent them and you admit and say that they belong to the lender, they remain his as though the loan has been canceled. And really, it still requires clarification why the original coins are different from any other coins.

When we learned this passage in yeshiva a few days ago, I thought to answer that Rashi means not necessarily the original coins; rather, as long as the borrower currently has some coins (original or not), once he partially admits, the coins are considered as though the lender has already received them. And if the borrower currently has enough coins to repay the entire loan that he admitted to, then this is “here it is” and he is exempt from the oath. According to this, it would come out that one can effect betrothal with a loan (when there is no denial regarding it) after the due date, if the borrower has money.

Conceptually, it is hard to accept that the mere existence of money turns it into “here it is” (as opposed to the existence of land—as Rabbi Akiva Eiger explains there). Rashi too writes that he says, “and they are yours wherever they are,” and perhaps there there is something akin to an act of giving. Without that, I have serious doubt whether even according to Rashi this counts as “here it is.” The medieval authorities there dispute which admissions count as “here it is,” and I do not recall anyone writing that the mere fact that the borrower has money counts as “here it is.”
Now I think that the Gemara on 5a, which says that all land is “here it is,” is clear proof against you. We see that only the existence of land with the borrower counts as “here it is,” whereas according to your argument, any property in his possession would be “here it is,” not specifically land.

As for the proof from land, I think it is phrased as an “all the more so” case. That is, one might have thought that when I lent you 100 shekels, I can return them through “here it is” only in shekels and not with something else like land; then the Gemara comes and teaches that even though I lent you 100 shekels (and not land), I can repay the debt through “here it is” with land worth 100 shekels (meaning that land counts like money for purposes of “here it is”). But as for “here it is” with ordinary money, that is obviously possible.

First, it is not brought in the Gemara as a novelty but as a question. Second, there is no novelty here at all: throughout the Torah, something worth money is like money. Third, land is the finest quality property (see Bava Kamma 7a regarding damages). If a novelty is needed, then the novelty would be that one can repay even with movable property or with money. With land it is obvious that one can.

In any case, even without entering into the question of which is preferable, land or money, the Gemara does not say that only the existence of land with the borrower counts as “here it is,” but that land is “here it is” (that is, it does not use the word “only”).

First, from the question itself it is already clear that the intent is specifically land (the Gemara asks why an exemption from oath is needed for land, and does not ask why there is any oath of partial admission at all). Second, all the medieval authorities there explained it that way. Third, this also clearly emerges from the Gemara’s answer, because if he dug pits, ditches, and caves in it, that is not “here it is.” Yet according to your view, that is still a case where he has land, even though the dispute is only about the damage to the land. If so, it is still unclear why an exemption from the oath of partial admission is needed for land, since he has land with which he can pay what he admitted to, and that should be “here it is.” And this also applies to the second answer, where he admitted to utensils and denied land—and again, that is a case where he has land (for otherwise there would be no “here it is” even without this).

As for the first part, the Gemara asks why an exemption for land is needed, since in any case there is no oath of partial admission (because “here it is” creates a situation where the borrower denies everything regarding the remainder of the debt).
As for pits, ditches, and caves, that is not “here it is” because the lender lent land in a certain condition, and he expects to receive it back in that same condition. If it was damaged, then money must be returned corresponding to its original value. The land after damage is no longer considered equivalent enough to money, and therefore it cannot be used as repayment of the loan.
As for admitting to utensils and denying land, that is a case where he has no land and he is not claiming “here it is”; otherwise, if he had land, he would use it to repay the debt and claim “here it is.”

The borrower denies the remainder of the debt, but there is the part he admits in land, and that is “here it is.” The question concerns only a situation where the part he admitted is land.
As for pits and ditches, damaged land has decreased in value, but it is itself still worth money. And if it is here, then according to your view that is “here it is.”
Admitting to utensils and denying land—he has the utensils. According to your view, that is “here it is” by virtue of their simply existing with him.

The logic of why “here it is” exempts is that we view the money of the “here it is” as though it had been returned to the lender before the claim, and what remains is only a claim over the remainder of the debt, regarding which the borrower denies everything. If the borrower currently has no money to return, we cannot view the money as though it had been returned before the claim, but if he does have money, then we can.
I came across a Meiri that supports my approach:
Beit HaBechirah (Meiri), tractate Bava Kamma 69a:
“As to what they said: if an object was stolen and the owners have not despaired, neither of them can consecrate it—this one because it is not his, and that one because it is not in his possession—from which you learn in any case that a person cannot consecrate that which is not in his possession, even though it is his. Some explain that this applies specifically to theft and the like, where the person refuses to give it back; and the same applies to a loan that he denies, or one that he withholds for some reason and does not wish to give. But something that he does not refuse to give, such as a loan that he admits, he may consecrate.”
It sounds from this Meiri that a loan which the borrower admits to is already in the lender’s possession, and therefore this is “here it is” (= “These coins, which he admits are included, are regarded as though the lender has already taken them”).
As for damaged land, true, it is worth money, but that is not enough money to cover the loan. Meaning: Reuven lent Shimon two fields worth one million shekels each. Reuven claims from Shimon the return of both fields. Shimon denies one field, and regarding the second he admits, but states that he damaged that field. Now the value of the field dropped from one million shekels to 900,000. So there is “here it is” on 900,000 shekels, and a remaining debt of 100,000 shekels regarding which he partially admits, and another million shekels which he denies. So there is still an obligation of the oath of partial admission here.
As for utensils, the Gemara itself treats the common case of a loan of utensils as “here it is,” because in most such cases they indeed claim “here it is” (unless the utensil broke/was lost/was stolen and the borrower has no money corresponding to it). If the utensil physically still exists with the borrower, this is excellent “here it is.”

The Meiri writes this also regarding theft that was admitted to. Therefore I am not sure there is proof from his words. But it is indeed an interesting source. In any case, I am almost certain you will not find a source saying that the mere existence of any property in the lender’s hands constitutes “here it is” (unless we are dealing with land). The plain sense of the Gemara also does not suggest that, as above.
Perhaps if he points to specific coins and is ready to give them, that is “here it is” according to the Meiri. But if he merely has money in hand—I seriously doubt that is what the Meiri means, as stated.
As for the two fields, I did not understand your words. He has two fields, each worth a million. He admits one and denies the second. In the one he admits, he dug pits and damaged it so that it is worth 900,000. So let him pay the remaining 100 from the field he denies—after all, it is in his possession. I remind you that according to your view, any property he has is “here it is,” even if it is not the specific property being claimed.
I also did not understand what you wrote regarding utensils. He is being sued for utensils and land; he admits the utensils and denies the land. He has the land he denied, and he can pay from it for the utensils he was sued for and admitted to. So according to your view, this is “here it is” because he has land in his possession.

As for the two fields, he sold the second field and consumed the money (used it up on pleasures). The same in the case of admitting utensils and denying land. So he cannot pay because he simply has no way to. If he did have a way to pay, and he is in any case admitting the 100,000, why would he not pay and exempt himself from the oath? It is in his interest.

At this point we are already getting into implausible forced readings, especially since none of the medieval authorities note this. The question why the defendant should not always say “here it is” always exists. Let him say it and be exempt.

When the defendant currently does not have enough money to pay the entire part that he admits to, he cannot say “here it is.”

Correct. But on the face of it, the discussion assumes that he does have it, unless you force a distant and strained reading.

As for the strained reading above (damaged land), it can be answered in another way:
When a person digs pits, ditches, and caves in land, a debt of the value of the land is created, and the value of land is treated like land. Meaning, the one who dug pits, ditches, and caves in it admits a debt of the value of land and denies something else (money, utensils, or land). The Gemara teaches that the very admission of a debt of the value of land exempts the debtor from the oath of partial admission, because it is like admitting land. In that case there is no “here it is,” because we are dealing with a debt for the value of land (the absence of land).

As far as I recall, the question whether the value of land is like land is a dispute between Maimonides and the Raavad in this Jewish law (whether damage payments are restoration of the prior state or compensation; the Shakh discusses this at length).
As for your suggestion, Rashi’s words there are a bit obscure, but as far as I recall everyone understood him to mean that two parcels of land were claimed, and in the one that the defendant admitted to, pits had been dug. If so, the second parcel of land, which he denies, stands for payment, and according to your view that is “here it is.” You can explain him against all the medieval and later authorities and say that there is only one claim of land here, except that now it is damaged in his possession, and he admits the land and denies the pits. But that is odd: if he admits that the land belongs to so-and-so, what is the dispute about the pits? Is he claiming that this is how it was originally? All this is very strange. More than that: Rashi explains that we are dealing with denial of land, not admission of land, and for that the novelty is needed that one does not take an oath over land. But according to your view, even for this the novelty is not needed, because even with movable property that he denies he does not swear if it is with him. And so again we are back to the forced reading that he does not have what he denies. All this is very far-fetched in my humble opinion, and certainly nobody learned it this way. Therefore, at least according to all the medieval and later authorities who learned Rashi in the normal way, the difficulty remains, and apparently they do not see this as “here it is.”

Continuing the matter of whether the loan is in the lender’s possession or the borrower’s, today I thought of a proof that after the due date the loan returns to the lender’s possession, based on a “since” consideration: since the lender could have transferred the money to the borrower for a fixed term (that is, transferred it to him for a year, say), and in that form after the term ended the money would revert to the ownership and possession of the lender, so too even without stating this explicitly, presumably he intends that after the due date the money should return to being his and in his possession (an implicit stipulation). It is like a gift on condition that it be returned after x time.

I think the “since” is not relevant here. This is not a matter of credibility. What you mean is an implicit stipulation. But the Torah’s commandment of lending is to give the money completely (and repayment is a commandment). Therefore there is no implicit stipulation here, because a person does not act contrary to the Torah. Admittedly, if he explicitly stipulated, one could discuss whether that would be effective. But even that is debatable, because a gift on condition of return requires return by the borrower, and as long as he has not returned it, it is his. And a gift for a limited time is not a condition on a loan but a different kind of transaction. Beyond that, with a gift for a limited time he can transfer only those specific coins and cannot create a debt.

Today I came across a Rashi from which it sounds as though the loan money actually belongs to the lender even without an act of acquisition:
Rashi, tractate Bava Metzia 6a:
“Abaye said—the reason of our Mishnah is not like Rabbi Yohanan, for if we would suspect him of ‘go and seize your fellow’s cloak for nothing,’ we should suspect him regarding an oath. Rather, we are concerned that he may have an old loan against this person, and he recognizes in him that he has forgotten, and so he will deny it, and the other goes and seizes his cloak, and swears that he has in it the value of half of it, and this cloak is his—for even the cloak upon his shoulders is encumbered to him.”
I infer this from the words: “this cloak is his,” and the one who seizes it even swears that it is his.

Perhaps my point until now was not clear. I concede that this is indeed the accepted approach among the commentators and halakhic authorities (that the value of the loan belongs to the lender, and the meaning of “a loan is given to be spent” is only that there is no ownership over specific coins). My claim is only that there are proofs supporting the newer conception that the loan is not the lender’s (mainly in Maimonides’ view; there there are truly compelling proofs for this). So even if there are proofs from the medieval authorities, that does not contradict my basic claim. Proofs from the Talmud itself would of course be another matter.
But in this Rashi I do not see a clear proof against me. After all, it is obvious that there is a lien on assets against the loan, and what he is saying is that where there is a lien and he seizes against it, that is a situation in which he is as though seizing what is his. All the more so since here we are speaking of a case where he already attacked and seized (realized the lien), and after he seized the value of the loan, the money certainly does fully belong to him—just like money that the borrower pays him in repayment, where it is obvious that it fully belongs to him. My claim regarding the value of the loan is only so long as it has not yet been paid.