Gemara

We did not count Yovel from the time that Sancheriv exiled the 10 tribes, until Yirmeyahu returned them.

32b (Beraisa): "U'Kerasem Deror ba'Aretz l'Chol Yoshveha" teaches that Yovel applies only when all the residents (Bnei Yisrael) are in Eretz Yisrael.

Gitin 36a (Mishnah): Hillel enacted Pruzbul...

Question: If mid'Oraisa the loan is cancelled, could Hillel enact that it is not cancelled?!

Answer #1 (Abaye): The Mishnah is like Rebbi, who says that Shemitas Kesafim (cancellation of loans in Shemitah) is only mid'Rabanan nowadays.

(Beraisa - Rebbi): "V'Zeh Devar ha'Shemitah Shmot" discusses two Shemitos (abstentions), of money, and of land. Shemitas Kesafim applies exactly when Shemitah of land applies.

Chachamim enacted Shemitas Kesafim (nowadays) for a commemoration of Shemitah.

36b (Shmuel): If I had the power (if I were greater than Hillel), I would abolish Pruzbul.

37a (R. Yochanan and Reish Lakish): If there is a document with Acharayus, the loan is not cancelled.

Support (Beraisa): Shemitah cancels a loan document, but not if it has Acharayus.

A case occurred, and R. Yochanan ruled that the loan is cancelled.

R. Yochanan: Perhaps the Beraisa is like Beis Shamai, who consider a document as if were collected already.

37b (Mishnah): If Reuven returns a debt to Shimon in Shemitah, Shimon must say 'I refrain (from collecting)';

If Reuven says 'even so, I want to repay', Shimon may take the money.

We learn this from "this is Devar (the word of) ha'Shemitah".

(Rabah): Shimon may be Toleh (coerce) Reuven until Reuven says that he wants to repay anyway.

Question (Abaye - Beraisa): When he pays, he may not say 'I am paying the loan.' Rather, he says that it is a gift.

Answer (Rabah): Shimon is Toleh Reuven until he says this.

Aba bar Minyomi owed money to Rabah. He brought it to him in Shemitah.

Rabah: I refrain.

Aba took his money and left. Rabah was sad. Abaye heard what happened, and told Aba that he should have said that he wants to pay anyway, and that he should do so now. Aba did so.

Rabah: He did not know enough to do so the first time.

Avodah Zarah 9b (Rav Huna brei d'Rav Yehoshua): If one does not know which year of the Shemitah cycle it is (to write in the document)...

Rishonim

Rambam (Hilchos Shemitah 9:3): Mid'Rabanan, Shemitas Kesafim applies nowadays, even though Yovel does not apply nowadays, so that Yisrael will not forget the law of Shemitas Kesafim.

Hasagos ha'Ra'avad (on Rif Gitin 19b): Rabah taught that one may be Toleh the borrower. This is when Shemitah applies. In the days of Rabah, Rav Ashi and the later Amora'im, it (Shemitas Kesafim) was only Midas Chasidus, so the borrower need not say that it is a gift. Once he says 'I want to pay anyway', one collects immediately. Rabah taught this law, and once Aba said 'I want to pay anyway', he immediately took the money, and said that Aba was ignorant at first!

Question: Does Shemitas Kesafim applies nowadays? The Gemara connotes that it does, e.g. the Sugya of the enactment of Pruzbul. Rav Ashi gave to a borrower a palm stump in order to write a Pruzbul, and his Talmidim recited the text of Pruzbul in front of each other. Rabah did not press Aba for payment. All these Amora'im were in Bavel, and they conducted Shemitas Kesafim!

Answer (Rosh, Teshuvah 77:2): I ceased to write about Shemitas Kesafim since I came to this land (Toledo). I asked why they are not Meshamet Kesafim, and they said that the custom of this entire land is not to do so. We cannot Mevatel a long standing custom, for there are many old loans. They brought a proof from the text of their documents; it did not suffice for me. To justify their practice, I say that since this is the custom, everyone knows this, and it is as if the lender stipulated 'on condition that Shemitah will not cancel the loan.'

Note: Makos 3b says that it works only if he stipulates 'on condition that you will not cancel the loan in Shemitah.'

Rashi (Avodah Zarah 9b DH Hai): They write the year of the Shemitah cycle in the document, for Shemitah applies even nowadays. Even Rebbi agrees that it applies mid'Rabanan.

Ran (on Rif Gitin 20a DH v'Yesh): Some are lenient and say that nowadays Shemitas Kesafim does not apply at all, and we do not need a Pruzbul. They say that we hold like Rebbi, who says that Shemitas Kesafim applies only when Yovel applies. We see many leniencies in Pruzbul. This implies that Shemitah nowadays is mid'Rabanan. If it were mid'Oraisa, like Rabanan who argue with Rebbi, we would not be so lenient. Since mid'Oraisa Shemitah depends on Yovel, also mid'Rabanan it applies only when Yovel applies. In the days of Raboseinu a Beis Din was fixed in Eretz Yisrael. It was Mekadesh Yovel and blew the Shofar. They freed slaves and returned fields to the initial owners, to commemorate Yovel. Therefore, Shemitah applied mid'Rabanan, both for land and loans. Nowadays, no Beis Din is Mekadesh and blows the Shofar. Yovel does not apply at all, for these things are Me'akev Yovel (Rosh Hashanah 8b). Since Yovel is Batel even mid'Rabanan, also Shemitah does not apply at all.

Rebuttal (Ran): Hillel (Rashi's grandson) fixed the calendar for all generations. Since then, there was no Beis Din in Eretz Yisrael that could be Mekadesh. All the more so, in the days of Rav Ashi there were no experts in Eretz Yisrael. Even so, he and Rabanan of his generation toiled to write Pruzbuls. Therefore, Shemitas Kesafim applies everywhere and at all times. However, it is only mid'Rabanan, like Rebbi, since we find that we are very lenient about laws of Pruzbul.

Rashba (Teshuvah 3:32): Here and in all lands of our exile, we conduct Shemitas Kesafim. The Ge'onim ruled like this. The Rif brought the entire Sugya, and Rashi in Avodah Zarah says so. Amora'im in Bavel nowadays (after the Churban) were Meshamet Kesafim. The Yerushalmi says that nowadays that there is no Yovel, Shemitah is mid'Rabanan. If Shemitah of land is mid'Rabanan in Eretz Yisrael, Shemitas Kesafim applies everywhere mid'Rabanan.

Terumas ha'Deshen (304): Even though the Ri, R. Tam and Rashi (Avodah Zarah 9b DH Hai) hold that Shemitas Kesafim applies nowadays, Rabanan in our generations rule that it applies now. I heard one say that it is astounding to say that Shemitas Kesafim should exempt from a loan. Even the one who said that Shemitah applies, said so only if he had other excuses. The Tur (CM 67) says that the Rosh screamed to abolish the custom not to cancel loans, but no one heeded him. The text of their documents gives the lender power to force the borrower to pay 'in any way, whether according to law or not.' The Rosh said that this does not help, for it is a stipulation contrary to Torah! We can say that they hold like Rebbi. A commemoration for Shemitah was made only near Eretz Yisrael, e.g. Bavel and Mitzrayim. The Ri (Avodah Zarah 59a DH Betzer) says that this is why Terumah and Ma'aser do not apply in our lands. Chalah applies elsewhere, for it is like an obligation on the owner of the dough, whereas Terumah is incumbent on the owner of the land. All the more so, Shemitas Kesafim, which is an obligation on the person, should apply everywhere! However, we can say that Shemitas Kesafim is like Shemitah of land. Both depend on Kedushas Shemitah. In Kidushin, we needed a verse to teach that Shemitas Kesafim applies in Chutz la'Aretz. Even after the verse includes it, it is like an obligation on the land. R. Tam wrote a Pruzbul. He disagrees with the Ri's answer about Terumah; we can say the same for the Rosh. For the Isur Torah of Kil'ayim, later generations were lenient like R. Yoshiyah against Stam Mishnayos. All the more so, for a commemoration of Shemitah we may rely on a Gaon's (the Ri's) answer, even though earlier Ge'onim did not. In Makos (3b), we say that only a stipulation that the borrower pardon the law of Shemitah helps. The text of their documents does not connote pardon.

Bach (CM 67:5): We do not follow a custom against the Torah! Normally, Chachamim can enact monetary laws. Here, since Hillel already enacted Pruzbul, we cannot totally abolish Shemitah. Shmuel said that he cannot abolish Pruzbul. All the more so we cannot abolish Shemitah! Perhaps the custom is like Rav Nachman, who said that he would enact that Pruzbul is not needed. This is wrong. Rav Nachman said 'if I had the power'! Rav Ashi's Talmidim did not rely on Rav Nachman. The Rosh (Gitin 4:13) says that Rav Nachman only meant to exempt from writing a Pruzbul document, but the lender would need to recite its text in front of Beis Din. Surely he did not intend to uproot Shemitah (mid'Rabanan). He could not, for it was enacted by (earlier) Chachamim greater than himself! The Rambam and Semag say like the Ri, that Terumah is only in lands near Eretz Yisrael, yet they say that Shemitas Kesafim applies everywhere nowadays! Surely the Ri agrees. Maharik (92) says that a document destined to be collected is as if it was already collected. The Mordechai (Yevamos 52) says so; for this, we hold like Beis Shamai. This is astounding. R. Yochanan retracted, and cancelled a document with Acharayus, for the Beraisa that says otherwise is like Beis Shamai! The Poskim rule like this. The Mordechai merely explained Beis Shamai.

Gra (67:6): Maharik is wrong. Everywhere we rule (even about this) unlike Beis Shamai.

Bach (5): Even if we would say (that the Halachah follows Beis Shamai), Kesuvah is different, for it is an enactment of Beis Din, or to promote marriage. Rather, since a lender is believed to say that he had a Pruzbul and lost it, the borrower does not want to take the lender to Beis Din, since it is futile. Also the lender relies on this not to write a Pruzbul, since he will be believed. One who is stringent to do properly will be blessed

Tosfos (36b DH v'Tikun): Chachamim enacted Shemitas Kesafim mid'Rabanan, but not Yovel mid'Rabanan, because most of the Tzibur could not fulfill two consecutive years in which one may not work the land. (Note: the SMA's text connotes that Tosfos asked why Chachamim did not enact to forbid working the land in Shemitah and Yovel.

SMA (2): Only when Shemitah and Yovel were mid'Oraisa, there was a Berachah that the sixth year would produce for three years. I would answer differently. The Kedushah (regarding working the land) applies only to Eretz Yisrael, therefore no enactment was made for it. Shemitas Kesafim is obligatory on people (so it was enacted everywhere).

Poskim

Shulchan Aruch (CM 67:1): Shemitas Kesafim applies mid'Oraisa only when Yovel applies. Mid'Rabanan Shemitas Kesafim applies nowadays everywhere.

Rema: This is like the consensus of Poskim, but some say that Shemitah does not apply nowadays. People rely on them in our lands. Shemitas Kesafim is not practiced at all. This was from the days of the Rosh. He screamed to abolish it, but no one heeded him. The Acharonim gave reasons for the custom; we do not question them.

Beis Yosef (DH v'Hashmatas): Also Ba'al ha'Itur rejected the proofs of those who are lenient. Sefer ha'Terumah brought a Teshuvah of the Ba'al ha'Ma'or who justified the custom not to be Meshamet Kesafim in Chutz la'Aretz nowadays, and that the Ramban holds that it applies. He concluded that the Ra'avad retracted and said that it applies, and so says Rashi. There is no Safek about this.