Rif Bava Kamma 34a {96b}

34a

{Bava Kamma 96b}

ואמר רב פפא האי מאן דגזל נסכא מחבריה ועבדה זוזי לא קני
מ"ט הדר עביד לה נסכא
זוזי ועבד להו נסכא קני
מאי אמרת הדר עביד להו זוזי הנהו זוזי אחריני נינהו

שמעינן מהא דרב פפא דשינוי החוזר לברייתו לא הוי שינוי
ולפיכך לא קני
וכן הלכתא
הלכך מתני' דקתני הגוזל עצים ועשאן כלים משלם כשעת הגזילה עצים ושיפן נינהו כגון בוכאני
וכדאוקמא רב אשי דהוא בתרא:

And Rav Pappa said: If one misappropriated bullion of silver from another and converted it into coins, he would not acquire title to them. What is the reason? He could again convert them into bullion. If out of coins he made bullion he would acquire title to it. What will you say? That he can again convert them into coins, these are other coins.

We deduce from this of Rav Pappa that a change which can be returned to its natural state is not a change, and therefore he does not acquire.
And so is the halacha.
Therefore, our Mishna which teaches IF ONE MISAPPROPRIATES PIECES OF WOOD AND MAKES UTENSILS OUT OF THEM ... HE HAS TO PAY FOR THEM IN ACCORDANCE WITH [THEIR VALUE AT] THE TIME OF THE ROBBERY, these are pieces which he planed, such as clubs {see Bava Kamma 93b}, and as Rav Ashi establishes it, for he is later.

זה הכלל כל הגזלנין משלמין כשעת הגזלה
כל לאיתויי מאי לאיתויי הא דאמר רבי אלעאי דאמר רבי אלעאי גנב טלה ונעשה איל עגל ונעשה שור נעשה שינוי בידו וקנאו טבח ומכר שלו הוא טובח ושלו הוא מוכר:

"THIS IS THE GENERAL PRINCIPLE: ALL ROBBERS HAVE TO PAY IN ACCORDANCE WITH [THE VALUE OF THE MISAPPROPRIATED ARTICLES AT] THE TIME OF THE ROBBERY":
"All" is to include what? To include that which Rabbi Illai said. For Rabbi Illai said: If a thief misappropriated a lamb which became a ram, or a calf which became an ox, as the animal underwent a change while in his hands he would acquire title to it, so that if he subsequently slaughtered or sold it, it was his which he slaughtered and it was his which he sold.

ההוא גברא דגזל תורי מחבריה
אזל כרב בהו כרבא וזרע בהו זרע
לסוף אהדרינהו למרייהו
אתא לקמיה דרב נחמן
אמר להו זילו שומו שבחא דאשבח
אמר ליה רבא תורי אשבח ארעא לא אשבח
אמר ליה פלגא שבחא קאמינא
אמר ליה סוף סוף גזלה היא והדרה בעינה דתנן כל הגזלנין משלמין כשעת הגזלה
אמר ליה האי איניש גזלנא עתיקא הוא ובעינא דאיקנסיה

מהא שמעינן דקנסינן בכי האי גוונא ואפי' בחוץ לארץ דהא רב נחמן בבבל הוה וקא קנס
ועוד דגרסינן בפרק נגמר הדין
תניא אמר רבי אליעזר בן יעקב שמעתי שבית דין היו מכין ועונשין שלא מן התורה ולא לעבור על דברי תורה אלא לעשות סייג לתורה:

There was a certain person who stole a yoke of oxen from his fellow went and did some ploughing with them and also sowed with them some seeds and at last returned them to their owner. It came before Rav Nachman. He said to them: Go forth and appraise the increment {to the field}. Rava said to him: Were only the oxen instrumental in the increment, and did the land contribute nothing to the increment?
He {=Rav Nachman} said to him: I surely meant only half of it.
He {=Rava} said to him: In the end anyway, since the oxen were misappropriated they merely have to be returned intact, as we have indeed learnt: ALL ROBBERS HAVE TO PAY IN ACCORDANCE WITH [THE VALUE] AT THE TIME OF THE ROBBERY.
He {=Rav Nachman} said to him: That person is a notorious robber, and I want to penalize him.

From here we derive that we fine in such a case, and even outside the land {of Israel}, for Rav Nachman was in Bavel and he fined. And furthermore, we learned in perek Nigmar HaDin: They learnt {in a brayta}: Rabbi Eliezer ben Yaakov said: I heard that a bet din can hit and impose penalties not from the Torah, and not as a violation of the words of the Torah, but in order to make a fence for the Torah.

Mishna:

גזל בהמה והזקינה עבדים והזקינו משלם כשעת הגזילה
ר' מאיר אומר בעבדים אומר לו הרי שלך לפניך

גזל מטבע ונסדק פירות והרקיבו יין והחמיץ משלם כשעת הגזילה
גזל מטבע ונפסל תרומה ונטמאת חמץ ועבר עליו הפסח בהמה ונעבדה בה עבירה או שנפסלה מעל גבי המזבח או שהיתה יוצאה ליסקל אומר לו הרי שלך לפניך:

IF ONE MISAPPROPRIATED AN ANIMAL AND IT BECAME OLD, OR SLAVES AND THEY BECAME OLD, HE WOULD HAVE TO PAY ACCORDING TO [THE VALUE AT] THE TIME OF THE ROBBERY. RABBI MEIR SAYS: IN THE CASE OF SLAVES HE MIGHT SAY TO THE OWNER: HERE, TAKE YOUR OWN.

IF HE MISAPPROPRIATED A COIN AND IT BECAME CRACKED, FRUITS AND THEY BECAME STALE OR WINE AND IT BECAME SOUR, HE WOULD HAVE TO PAY ACCORDING TO [THE VALUE AT] THE TIME OF THE ROBBERY.
IF THE COIN WENT OUT OF USE, THE TERUMAH BECAME DEFILED, THE LEAVEN FORBIDDEN [FOR ANY USE BECAUSE] PASSOVER HAD INTERVENED, OR IF THE ANIMAL [HE MISAPPROPRIATED] BECAME THE INSTRUMENT FOR THE COMMISSION OF A SIN OR IT BECAME OTHERWISE DISQUALIFIED FROM BEING SACRIFICED UPON THE ALTAR, OR IF IT WAS TAKEN OUT TO BE STONED, HE CAN SAY TO HIM: 'HERE, TAKE YOUR OWN.'