At 12:00 a.m. someone placed a box of nougat chocolate bars in the beis medrash for the talmidim who had stayed late to learn. Moshe was on a diet but went to get one for his chavrusa, David, who had gone back to his dorm room for a few minutes to get a sefer.

While he was standing there, Moshe got into a discussion with one of his friends. He put the chocolate bar down on the table next to the box. Meanwhile, Aryeh came by. He looked in the box, but it was already empty. He saw the bar lying next to the box and took it.

Moshe noticed him taking it. “I’m sorry,” he said to Aryeh. “I already took that bar for my chavrusa, David.”

Aryeh looked at him skeptically. “I’m not sure it was fair to take for him when there weren’t enough for the people who are here now!” he said. He put the chocolate bar down.

“David is also entitled, since he is also learning,” Moshe replied. “He’ll be back in a few minutes. Anyway, I didn’t take one for myself, so I don’t see any problem taking for him.”

David returned five minutes later. “They put out nougat chocolate bars for the bachurim while you were gone,” Moshe said to him. “I took one for you.”

“Oh, thank you,” said David, “but I don’t want it. I’m allergic to nuts.”

Zvi, who was sitting nearby, overheard them. “I didn’t get one,” he said. “Can I have it?”

“Sure,” said David. He reached over and passed the chocolate bar to Zvi.

“Actually, Aryeh had wanted that bar,” Moshe commented. “He even picked it up, but I told him that I had taken it for you. Maybe he should get it?”

“Oh, I didn’t realize,” said David. “But I already gave it to Zvi. It’s his now.”

“I’m not sure,” said Moshe. “If you don’t want it, then maybe Aryeh has first rights.”

“Rabbi Dayan is still learning here,” said David. “Let’s ask him!”

Moshe, David, Aryeh and Zvi went over to Rabbi Dayan. Moshe related the story to Rabbi Dayan and asked, “Who does the chocolate bar belong to — Aryeh or Zvi?”

“In your case, the chocolate bar belongs to Aryeh,” Rabbi Dayan ruled. “Since David did not want the chocolate, it remained available for anyone to take and Aryeh’s acquisition is valid retroactively.”

“Can you explain more?” asked Aryeh.

“When the box of chocolate was put out to take from,” explained Rabbi Dayan, “Moshe was able to acquire a bar on behalf of David based on the principle of zachin l’adam shelo b’fanav — acquiring on behalf of someone even when he is not present. Thus, it would be David’s if he were interested in getting the chocolate” (C.M. and Shach 269:1).

“However, you cannot force someone to accept something that he does not want,” continued Rabbi Dayan. “If the recipient expresses disinterest in the item and says that he does not want it, the acquisition on his behalf is null and void retroactively. Thus, the chocolate bar was available when Aryeh initially picked it up, so he acquired it” (C.M. 243:1).

“What if Aryeh hadn’t picked it up?” asked Moshe. “Let’s say he had just asked me about it while it was sitting on the table.”

“Then it would remain hefker and be available to whoever takes it now,” replied Rabbi Dayan. “It would then belong to Zvi, who has it now.”

“What about a slightly different case,” said Moshe. “Let’s say that the box was not left out as hefker, but someone had given me the chocolate bar for David and he didn’t want it. Could I then keep it for myself?”

“In that case, when you accepted a gift from someone on behalf of David and he didn’t want it, you should return it to the giver,” replied Rabbi Dayan. “He did not make it available to everyone, only to the intended recipient. If the recipient doesn’t want it, it remains the property of the giver” (C.M. 245:10; Pischei Choshen, Kinyanim 15:27).