Rabbi Dayan was approached by four avreichim (rabbinical students) in his kollel.

“I joined the kollel last month and took a seat vacated by Moshe a few months earlier,” Reuven said. “Yesterday, I reached into the shelf under my table and found $40 there. There was also a note written by Aharon, ‘$40 for purchase of sefarim.’ You see, Moshe sells sefarim for $40.”

“The money was apparently paid when Moshe sat there,” noted Rabbi Dayan.

“That’s what I thought, so I returned the money to Aharon,” continued Reuven. “But this morning, Shimon, who owes me $40, told me that he left $40 for me under my table last week! Now I don’t know whether the $40 was connected to the note or was the repayment from Shimon!”

“When did you place the money and the note there?” Rabbi Dayan asked Aharon.

“At least three months ago,” Aharon replied.

“Did you reach into the shelf during the month you were here?” Rabbi Dayan asked Reuven.

“I reached into the shelf a number of times, but never noticed the money,” replied Reuven. “It wasn’t very deep, so it’s not likely that I would have missed it. On the other hand, Shimon insists that the note has been there three months, and I never noticed it!”

Rabbi Dayan turned to Moshe. “Did you receive the $40?” he asked.

“I don’t remember,” replied Moshe. “My records are not 100 percent accurate.”

“Assuming that you all trust each other and are telling the truth, there are two possibilities,” said Rabbi Dayan. “One is that the $40 is connected to Aharon’s note and has been sitting there for the past few months, whereas the money that Shimon put there last week got lost.

“The other possibility is that Reuven found the $40 that Shimon left for him,” continued Rabbi Dayan. “Aharon’s money from three months ago was either already taken by Moshe, who accidentally left the note there, or was lost. Where is the money now?”

“Reuven gave it back to me,” replied Aharon. “I’m now holding it. What should I do with it?

“The Gemara (B.M. 26a) teaches that if someone moves into an apartment and finds items,” replied Rabbi Dayan, “he can assume that they belong to the tenant who immediately preceded him. However, if the items were hidden in a crevice, they may belong to a prior tenant” (C.M. 260:3; Shach 260:11).

“Thus, if Reuven reached into the shelf a number of times to take out things and never found the money until now,” continued Rabbi Dayan, “we have to assume that the money was recently placed there by Shimon, and it should be returned to Reuven. Although Aharon’s note was also just discovered now, it’s much easier to miss a small slip of paper than bills of money.”

“What about the $40 for the sefarim?” asked Aharon. “Do I have to pay Moshe again?”

“If one who owes money placed it in the lender’s property and notified him, or it was fully secure, he has fulfilled his repayment obligation,” replied Rabbi Dayan. “However, the shelf under the table is not secure, so unless you informed Moshe that the money was there, it is not valid repayment if the money got lost” (see Aruch Hashulchan, C.M. 120:2; Pischei Choshen, Halva’ah 5:1[2]).

“It’s possible, though,” acknowledged Moshe, “that I received the money.”

“When neither party knows whether a debt was repaid, the borrower has no legal obligation to pay,” said Rabbi Dayan. “The authorities dispute whether there is a moral obligation to pay, or at least compromise with, the other party. Thus, at most, Aharon should pay partially as a moral obligation” (see C.M. Taz 75:10; Shach 75:65; Pischei Teshvuah 75:21).”

“So where does that leave us?” asked Aharon.

“The $40 should be given to Reuven, since almost definitely it was recently placed there,” answered Rabbi Dayan. “However, since there is a slight possibility that the $40 was left by Aharon and he is currently in possession of it, he can retain some, let’s say $10, to settle with Moshe, and Shimon should fill in that difference to Reuven.”