We have seen in the previous sections that the prohibition of Hotza’ah includes transporting an object more than four amot in a public domain, since one’s personal space within the public domain is defined as four amot. If he transports an object further, he is deemed to have moved it to a different domain and transgressed Torah law. But within a square of four amot by four amot one may carry. Therefore, only one who carries something a distance greater than the diagonal of a four-amot square (2.58 m) has violated a Torah prohibition, because only then is it clear that he carried outside the permissible area.
By Torah law, one who wants to transport an object within a reshut ha-rabim may carry it a bit less than four amot, stand still in order to establish a new location for the object, then walk again for less than four amot. He can continue in this way – starting and stopping – until he has transported the object wherever he wants it. However, the Sages forbade this lest one end up carrying more than four amot and thus violate Torah law. Even in a karmelit, which is considered a reshut ha-rabim only rabbinically, they forbade carrying an object less than four amot out of concern that one might come to carry more than four amot in a reshut ha-rabim.
However, one who stands to lose his money, such as one who is traveling with a large sum of money when Shabbat begins and has no safe place to hide it, and no non-Jew is available to guard the money or transport it to his home, then in order to prevent his suffering a financial loss the Sages permit the Jew to carry his backpack in the manner discussed in the previous paragraph – starting and stopping, and making sure to walk less than four amot each time (paĥot paĥot mi-daled amot). He may continue this way until he reaches a place where he can safely leave the money. This permission applies even in a reshut ha-rabim. In a karmelit, one may generally carry this way for the sake of a mitzva (SA 266:7, 8; BHL 349:5).
. According to many poskim (Raavad, Ha-Ma’or, Rosh, and others), if many people are there, it is permitted le-khatĥila for each one to carry an item fewer than four amot and pass it to the next person, who will also carry it less than four amot. Using this method, they can transport the object across great distances. Pri Megadim allows this even when there are only two people involved, as long as each one carries the item less than four amot before passing it back to the other person. In contrast, some Rishonim prohibit doing this even with many people (Ramban). These positions are cited by SA 349:3 and BHL s.v. “va-ĥavero.” The Sages permitted carrying tefilin on Shabbat in this manner, if it is necessary in order to keep them safe (SA 301:42).
. If the person who did not make it home before the start of Shabbat was walking nonstop from before Shabbat began, there is another possible solution. He can run until he arrives at his home. Since the akira of the object was done before Shabbat began, in any case he will not violate Torah law. In order to save his money, the Sages allowed him to run to his house, even though this involves transporting an item to a different reshut (ha’avara) and setting it down there (hanaĥa), which are normally prohibited. They ruled that he should run, to ensure that he does not make the mistake of stopping (Shabbat 153b: “He should run, not go gently [i.e., walk]. Why? Since there is nothing to remind him, he may end up performing akira and hanaĥa”). If possible, upon arrival in the reshut ha-yaĥid, he should take off his backpack with a shinui, so as to minimize the prohibition as much as possible (SA 266:11).