Rif Gittin 19b {37a - b}

19b

{Gittin 37a}

תנן התם אין כותבין פרוזבול אלא על הקרקע אם אין לו מזכהו לתוך שדהו כל שהוא
וכמה כל שהוא
א"ר חייא בר אבא אמר רב אפילו קלח של כרוב
אמר רב יהודה השאילו מקום לתנור או לכירה כותבין עליו פרוזבול:

They learnt {tnan} over there {=elsewhere}: We do not write a prozbul except for upon land {which the debtor owns}. If he does not have land, we transfer over to him within his {=the creditor's} field a tiny amount.
And how much is a tiny amount?
Rabbi Chiyya bar Abba cited Rav: Even a stalk of carob.
Rav Yehuda said: Even if he lends him enough place for an oven or a stove, they write upon it a prozbol.

תנו רבנן אין לו קרקע ולערב יש לו קרקע כותבין עליו פרוזבול. לו ולערב אין לו קרקע ולדחייב לו יש לו קרקע כותבין עליו פרוזבול מדר' נתן
דתניא רבי נתן אומר מנין לנושה בחבירו מנה וחבירו בחבירו מנין שמוציאין מזה ונותנין לזה ת"ל ונתן לאשר אשם לו

The Sages learnt {in a brayta}: If he {=the debtor} does not have land but the guarantor has land, we write a prozbol upon that. If neither he {=the debtor} nor the guarantor has land, but someone who owes the debtor has land, we write upon it a prozbul, from Rabbi Natan's statement.
For they learnt {in a brayta}: Rabbi Natan says: How do we know that if someone is owed a maneh by his friend, and his friend in turn {is owed a maneh} by his friend, from where that we can take from this one and give to that one? Therefore it informs us {Bemidbar 5:7}:

ז וְהִתְוַדּוּ, אֶת-חַטָּאתָם אֲשֶׁר עָשׂוּ, וְהֵשִׁיב אֶת-אֲשָׁמוֹ בְּרֹאשׁוֹ, וַחֲמִישִׁתוֹ יֹסֵף עָלָיו; וְנָתַן, לַאֲשֶׁר אָשַׁם לוֹ.

7 then they shall confess their sin which they have done; and he shall make restitution for his guilt in full, and add unto it the fifth part thereof, and give it unto him in respect of whom he hath been guilty.

{Gittin 37b}

ש(אמר רב יהודה א"ר נחמן נאמן אדם לומר פרוזבול היה לי ואבד
מ"ט כיון דתקינו רבנן פרוזבול לא שבק היתירא ואכל איסורא
כי אתו לקמיה דרב אמר להו מידי פרוזבול היה לך ואבד
כגון זה פתח פיך לאלם):ש

(Rav Yehuda cited Rav Nachman: We believe a person to say "I had a pruzbol but it was lost."
What is the reason? Since the Sages enacted prozbul, he would not leave aside the permitted {food} and eat forbidden food.
When someone came before Rav, he said to him, "Did you have a prozbul and it was lost?"
Such as this is opening your mouth on behalf of he who is unable to speak.
{I, Josh, would note that it is not clear from this text whether the person actually did have a prozbol. Perhaps this was in accordance with leanings towards Rav Nachman, who would rather have it even without writing a prozbul.}
)