What determines our residence, where we eat or where we sleep?

“We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.” (Declaration of Independence)

The phrase Anan Sahadee (אֲנַן סָהֲדִי) which translates literally we are witnesses means idiomatically a self-evident truth. Today’s daf TB Eruvin 73 provides us with a self-evident truth when discussing eruv hatzerot and eruv tekhumim concerning what determines our residence, where we eat or where we sleep?

The Mishnah on TB Eruvin 72b presents us with a case where five brothers who live in the same courtyard as the father and eat meals in his house, but live in their own domiciles. What determines whether an eruv hatzerot is needed, the place where a person sleeps or the place where the person eats? If the place where a person eats determines the person’s residence, then in our case no eruv hatzerot is needed because the family is already unified. If the place where the person sleeps i.e. lives is the determining factor, then each of the brothers need to contribute to the eruv hatzerot. That is the debate between Rav and Shmuel. “The Gemara asks: What is considered one’s place of residence? Rav said: The place where he eats his bread, and Shmuel said: His place of sleep.” (Sefaria.org translation)

The Gemara cites different kinds of watchmen who sleep in the field and eat at home and only have 2000 amot Shabbat limit from where they sleep as proof that a person’s residence is where he sleeps supporting Shmuel’s position. This proof is rebuffed by citing a self-evident truth. “There, in the case of the people in the field, we are witnesses (אֲנַן סָהֲדִי), i.e., it is clearly evident, that if people would bring them bread there, to the place where they sleep, it would be more convenient for them. Fundamentally, however, a person’s dwelling place is determined by where he eats, rather than where he sleeps.” (Sefaria.org translation) The halakha is according to Rav’s position. A person’s residence is determined where he eats. (Shulkhan Arukh, Orekh Hayyim, 370:5)

“The Gemara addresses a similar issue with regard to a joining of Shabbat boundaries: Rav Ḥiyya bar Avin raised a dilemma before Rav Sheshet: With regard to students in their master’s house who eat their bread in their houses in the field [baga] and then come and sleep in their master’s house, when we measure their Shabbat limit for them, do we measure it for them from their master’s house, where they sleep, or do we measure it for them from the field, where they eat? He said to him: We measure it from their master’s house. Rav Ḥiyya bar Avin asked: But in the case of one who deposits his eiruv, which establishes the location of his meal, within two thousand cubits, and then goes back and sleeps in his house, we measure his Shabbat limit from his eiruv. This implies that the determining factor is where he eats, rather than where he sleeps.

“The Gemara answers: In that case we are witnesses (אֲנַן סָהֲדִי), and in this case we are witnesses (אֲנַן סָהֲדִי), i.e., in both cases the person’s intentions regarding his place of residence are clearly evident. In that case, where the person deposits his eiruv, we are witnesses that if he could reside there, at the site of his eiruv, it would be better for him, i.e., if he could spend the night there he would do so, since he wishes to continue from that place onward on the following day. And in this case of the students in their master’s house, we are witnesses that if people would bring them bread in their master’s house, enabling them to eat there, it would be better for them. Consequently, it is considered their place of residence.” (Sefaria.org translation)