Prosbol vs. Prozbol
The last few days in Gittin, we’ve been discussing Prozbol. That is how it is referred to in the modern day. Yet in the gemara itself, it seems to be called Prosbol, with a samech.
The Wikipedia entry in English is Prozbol with a z, and begins:
The Prozbul (Hebrew: פרוזבול, likely borrowed from Koinē Greek: προσβολή) was established in the waning years of the Second Temple of Jerusalem by Hillel the Elder. The writ, issued historically by rabbis, technically changed the status of individual private loans into the public administration, allowing the poor to receive interest-free loans before the Sabbatical year while protecting the investments of the lenders.
That Greek entry gives this etymology: From προσβάλλω (prosbállō, “to apply”) + -η (-ē).
The Hebrew Wikipedia entry also has the zayin, but notes the alternative spelling with a samech.
פְּרוֹזְבּוּל (נכתב גם פרוסבול, מיוונית: προσβολή) הוא תקנה הלכתית שנועדה לאפשר לגבות חובות של הלוואות שעבר זמן גבייתם ולא ניגבו, מבלי שמצוות שמיטת הכספים, הנוהגת בסוף שנת השמיטה, תגרום לביטול החוב. הפרוזבול ניתקן בידי הלל הזקן בסוף תקופת בית שני, והוא בשימוש נרחב גם בימינו. שמיטת הכספים האחרונה הייתה בכ"ט באלול ה'תשפ"ב, 25 בספטמבר 2022 והבאה תהיה בכ"ט באלול ה'תשפ"ט, 9 בספטמבר 2029.
In our gemara, Gittin 36a, we see it with a samech.
הִלֵּל הִתְקִין פְּרוֹסְבּוּל וְכוּ׳: תְּנַן הָתָם, פְּרוֹסְבּוּל אֵינוֹ מְשַׁמֵּט. זֶה אֶחָד מִן הַדְּבָרִים שֶׁהִתְקִין הִלֵּל הַזָּקֵן; שֶׁרָאָה אֶת הָעָם שֶׁנִּמְנְעוּ מִלְּהַלְווֹת זֶה אֶת זֶה, וְעָבְרוּ עַל מַה שֶּׁכָּתוּב בַּתּוֹרָה ״הִשָּׁמֶר לְךָ פֶּן יִהְיֶה דָבָר עִם לְבָבְךָ בְלִיַּעַל וְגוֹ׳״, עָמַד וְהִתְקִין פְּרוֹסְבּוּל.
§ The mishna taught that Hillel the Elder instituted a document that prevents the Sabbatical Year from abrogating an outstanding debt [prosbol]. We learned in a mishna there (Shevi’it 10:3): If one writes a prosbol, the Sabbatical Year 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 prosbol so that it would also be possible to collect those debts in order to ensure that people would continue to give loans.
and so on.
Why would the samech have switched to a zayin? I think that it is because of a phonological rule / process of consonant voicing and devoicing.
Among the phonemes, that is the sounds we produce, there are pairs of voiced and unvoiced consonants. By way of example, /s/ vs /z/, /t/ vs /d/, /p/ vs /b/, /f/ vs /v/, /k/ vs /g/. Try pronouncing each and you’ll get a feel for voiceless vs. voiced.
If you juxtapose a voiced consonant next to an unvoiced consonant, one could easily change to be more like the other. One famous example, from Yerushalmi Berachot 2:4:
רִבִּי לֵוִי רִבִּי אֶבְדִּימָא דְחֵיפָה בְשֵׁם רִבִּי לֵוִי בַּר סִיסִי צָרִיךְ לְהַתִּיז לְמַעַן תִּזְכְּרוּ. רִבִּי יוֹנָה בְשֵׁם רַב חִסְדָּא צָרִיךְ לְהַתִּיז כִּי לְעוֹלָם חַסְדּוֹ.
The first statement is that one needs לְהַתִּיז the zayin of תִּזְכְּרוּ. The second, a bit hard to understand, is that one needs לְהַתִּיז the samech in חַסְדּוֹ. (I didn’t provide the English translation, but I disagree with it. They suggest this means voicing it as in stressing the samech, as if there were a dagesh in it.)
I would interpret lehatiz not as specifically to make it the voiced version, but to carefully enunciate. Thus, in תִּזְכְּרוּ, following the zayin is an unvoiced kaf. It is easy to accidentally make it lemaan tiskeru, so that you should profit. Similarly, Rav Chisda (appropriate to be talking about chasdo) says you should correctly pronounce chasdo. After all, the daled after it is voiced, so it might drag along the samech making you pronounce it as a zayin, as chazdo.
So, for prosbol, the bet is voiced, unlike the unvoiced peh. This would drag along the samech and turn it into prozbol.
Besides the etymology in Wikipedia, Chazal offer their own etymology, that would seem to reinforce the samech over the zayin. Thus, Gittin 36b - 37a:
מַאי ״פְּרוֹסְבּוּל״? אָמַר רַב חִסְדָּא: פְּרוֹס בּוּלֵי וּבוּטֵי.
§ The Gemara asks: What is the meaning of the word prosbol? Rav Ḥisda said: An ordinance [pros] of bulei and butei.
בּוּלֵי – אֵלּוּ עֲשִׁירִים, דִּכְתִיב: ״וְשָׁבַרְתִּי אֶת גְּאוֹן עוּזְּכֶם״, וְתָנֵי רַב יוֹסֵף: אֵלּוּ בּוּלָאוֹת שֶׁבִּיהוּדָה. בּוּטֵי – אֵלּוּ הָעֲנִיִּים, דִּכְתִיב: ״הַעֲבֵט תַּעֲבִיטֶנּוּ״. אֲמַר לֵיהּ רָבָא לְלָעוֹזָא: מַאי פְּרוֹסְבּוּל? אֲמַר לֵיהּ: פּוּרְסָא דְמִילְּתָא.
Bulei, these are the wealthy, as it is written: “And I will break the pride of your power” (Leviticus 26:19), and Rav Yosef taught with regard to this verse: These are the bula’ot, the wealthy people, of Judea. Butei, these are the poor, who are in need of a loan, as it is written: “You shall not shut your hand from your needy brother; but you shall open your hand to him, and you shall lend him [ha’avet ta’avitenu] sufficient for his need” (Deuteronomy 15:7–8). Therefore, the prosbol was instituted both for the sake of the wealthy, so that the loans they would give to the poor person would not be canceled, and for the sake of the poor, so that they would continue to find those willing to lend them money. Rava said to a foreigner who spoke Greek: What is the meaning of the word prosbol? He said to him: It means the institution [pursa] of a matter.
These might be real, or else folk etymology. It doesn’t matter. All that matters is that it is based on a samech rather than a zayin. By the way, the first etymology is from Rav Chisda, who we know knows about careful pronunciation, as above.
Finally, we can turn to manuscripts. All the manuscripts on Hachi Garsinan have samech in prosbol save one, Firkowitz 187.
So, what of the etymology that Rav Chisda provided?
He interprets it not as פְּרוֹס בּוּלֵי וּבוּטֵי, but פְּרוֹ זְבוּלֵי וּבוּטֵי. This is obviously inconsistent, because immediately after it, the gemara, even in this manuscript, finds Biblical basis for bulei, not zevulei, and butei. Meanwhile, Rava’s etymology clearly relies on the samech.
This doesn’t definitively prove that the zayin is wrong. As discussed above, Chazal were well aware of the process of consonant voicing and devoicing, such that they warned about it for parts of davening. In their etymology, they might have simply allowed for a Hebrew zayin to be based on an underlying samech.