The house was awhirl preparing for the “three-day” Yom Tov — Thursday and Friday, then Shabbos. The aroma of challah, meat and chicken wafted from the kitchen. The whir of the vacuum cleaner competed with the hum of the washer. The older children ran in and out doing errands.

Rabbi Dayan took a break from the preparations to go over his drashos (sermons) for Rosh Hashanah and to review the laws of shofar blowing.

When he finished, Rebbetzin Dayan paused for a moment from her cooking and cleaning. “Don’t forget to make the eruv tavshilin,” she gently reminded him.

“Of course,” replied Rabbi Dayan. “I’ll take care of it now.”

Rabbi Dayan took a challah and some cooked eggs. He called over his fifteen-year-old son, Aharon. “Could you please ask your friend Chaim to come and help me with the eruv tavshilin?”

Aharon went next door and returned two minutes later with Chaim.

“Thank you for coming,” Rabbi Dayan said to Chaim. “I’d like you to help me make the eruv tavshilin.”

“Sure, what do I have to do?” asked Chaim.

“Right now the challah and eggs are mine,” said Rabbi Dayan. “I want you to acquire them on behalf of all the Jewish people in the community, so that the whole community will have a share in them. Please take the challah and eggs and raise them at least a tefach (about four inches).”

Chaim raised the challah and eggs. Rabbi Dayan then took them from him, made the brachah and recited the declaration enacting the eruv tavshilin.

Chaim looked at Rabbi Dayan with a puzzled expression. “My father also just made an eruv tavshilin and didn’t give it to anyone,” he said. “Why did I have to pick it up? Besides, you have your own children here. Why couldn’t Aharon do it?”

“Most people make the eruv tavshilin only for their own household,” Rabbi Dayan explained. “Even though the standard version in the siddur or machzor states, ‘for us and all Jewish people living in this city,’ it is not really intended for others. However, the Rav truly intends it for the entire community in case someone forgets or is unable to make his own, and this covers that person on a one-time basis. I needed you to acquire the challah and eggs on behalf of the entire community, since the eruv tavshilin must be made with one’s own food” (O.C. 527:9-11).

“But only I picked up the food, not anyone else!” Chaim said.

“There is a well-known principle in monetary Halachah, ‘zachin l’adam shelo b’fanav’ — it is possible to acquire for someone [even] not in his presence,” answered Rabbi Dayan. “Thus, when you picked up the challah and eggs you acquired them not only for yourself, but also for the other townspeople, so that everyone will share in this eruv tavshilin” (C.M. 243:1).

“Why did I have to call Chaim over?” asked Aharon. “Why couldn’t I do it?”

“For a transaction to be valid, the item must move from the possession of one to the possession of another,” explained Rabbbi Dayan. “Since a father has certain monetary rights in the acquisitions of his children, the children are not considered independent entities. Had you raised the eruv food, it would be almost like transferring it from my right hand to my left hand. Therefore, I needed someone who is not a household member” (M.B. 366:55).

“Even an older child is insufficient?” asked Aharon. “I’m already bar mitzvah!”

“The Gemara (Eruvin 79b; B.M. 12a-b) differentiates between younger and older children,” replied Rabbi Dayan. “There is a dispute whether this distinction is between children before and after bar-mitzvah or between children financially dependent and independent. Since you are still financially dependent, it is preferable to have someone like Chaim, who is not a household member, acquire the food for the community. If we had married children here, they could accept the eruv” (C.M. 270:2; O.C. 366:10).