Bavli Gittin
[The mishnah taught that] Hillel [the Elder] instituted a document that prevents the sabbatical [year] from abrogating an outstanding debt [prosbul]. We learned [in a mishnah]: [if one prepares—Ed.] a prosbul, [the sabbatical year—Ed.] does not abrogate [debt]. This is one of the matters that Hillel the Elder instituted because he saw that [the people of] the nation were refraining from lending to one another [around the time of the sabbatical year, as they were concerned that the debtor would not repay the loan], and they violated that which is written in the Torah: Beware that there be not a base thought in your heart, [saying, “The seventh year, the year of release, is at hand”; and your eye be evil against your needy brother, and you give him nothing](Deuteronomy 15:9). He arose and instituted [the] prosbul [so that it would be possible to collect those debts in order to ensure that people would continue to give loans]. And this is the essence of the [prosbul]: I transfer to you, so-and-so judges, who are in such-and-such a place, [so] that I will collect any debt that I am owed by so-and-so whenever I wish, [as the court now has the right to collect the debts]. And the judges or the witnesses sign below. [The creditor will then be able to collect the debt on behalf of the court, and the court can give it to him.]
But is there anything [like this], where by Torah law the sabbatical [year] cancels [the debt] but Hillel instituted that it does not cancel [the debt]? Abaye said: [The baraita is referring] to the sabbatical [year] in the present; it is [in accordance with the opinion of] Rabbi. As it is taught, Rabbi says: And this is the manner of the abrogation: He shall abrogate (Deuteronomy 15:2). The verse [with its two occurrences of a term of abrogation—Ed.] speaks of two [types of] abrogation: One [is] the release of land and one [is the] abrogation of monetary [debts, thereby linking the two together—Ed.]. At a time when you release land [in the Jubilee year—Ed.], you abrogate monetary [debts]; at a time when you do not release land, [such as the present time, after the destruction of the Temple, when the Jubilee release of lands is not practiced—Ed.], you do not abrogate monetary [debts]. And the sages instituted that [despite this, the sabbatical year still] will abrogate [debt in the present, in] remembrance of the [Torah-mandated] sabbatical. Hillel saw that the nation refrained from lending to each other [so] he arose and instituted [the] prosbul.
But is there anything [like this], where by Torah law the sabbatical [year] does not cancel [the debt], and the sages instituted that it will cancel? Abaye says: It is [a case of—Ed.] “sit [passively] and not do [anything.” The sages have the authority over acts of omission, i.e., passively failing to fulfill a Torah law, as long as no action is taken—Ed.]. Rava says: Property [declared] ownerless [by] the court [is] ownerless. As R. Isaac says: From where [is it derived] that property [declared] ownerless [by] the court [is] ownerless? As it is stated: And whoever did not come within three days according to the counsel of the princes and the elders, all of his property shall be forfeited, and he shall be separated from the congregation of the captivity (Ezra 10:8). R. Eliezer said: [We derive it—Ed.] from here: These are the inheritances, which Eleazar the priest, and Joshua the son of Nun, and the heads of the fathers’ houses distributed for inheritance (Joshua 19:51). What do the heads have to do with the fathers? [It comes] to tell you: Just as fathers transmit anything that they wish to their children, so too, heads [of the nation] transmit to the people anything that they wish.
Published in: The Posen Library of Jewish Culture and Civilization, vol. 2: Emerging Judaism.