Question: Must one turn off one’s fax machine or answering machine on Erev Shabbat so that one does not receive any faxes or messages on Shabbat?
Answer: We have already explained in a previous Halacha that there is no prohibition regarding a forbidden work started before the onset of Shabbat which concludes on Shabbat itself, for no forbidden work is being performed by the individual on Shabbat. It is therefore permissible to turn on water sprinklers slightly before the onset of Shabbat although the watering of the plants or the lawn will continue on its own during Shabbat itself. It seems that the same should apply in our situation: Since the owner of the fax machine is not performing any forbidden action on Shabbat, it seems that he should not be obligated to turn off the fax machine before Shabbat. The same applies to an answering machine, a computer, or any other machine left on throughout Shabbat during which time messages and emails are received on these various machines (besides for radios and televisions which may not be left on during Shabbat for other reasons we shall not discuss here).
In a place where most residents are non-Jews, there is certainly room for leniency, for the one sending the fax or message on Shabbat is likewise not transgressing any prohibition since non-Jews are not commanded to observe Shabbat. However, there is room for discussion in a place where most of the population is Jewish since leaving one’s fax machine on causes the Shabbat desecration of the individual sending the fax.
Maran Rabbeinu Ovadia Yosef zt”l writes that even in a place where most of the population is Jewish, there is no obligation to turn off one’s fax machine before Shabbat, for we are not obligated to set forth enactments on every individual so that another Jew does not desecrate the Shabbat. If this was the case, we must likewise obligate every individual to turn off their telephones before Shabbat lest another Jew call them on Shabbat; there is no one who acts stringently regarding this matter at all and the reason for this is because one is not responsible for the Shabbat desecration another Jew may perform by calling him on Shabbat. The same law would apply to fax and other machines in that one need not turn them off before Shabbat. Similarly, according to the letter of the law, one may read or listen to faxes or messages sent to one’s machine on Shabbat; however, one who acts stringently and does not derive benefit from a work performed on Shabbat is especially praiseworthy.
At this point, we should not that it is permissible for a resident of Israel to send a fax to his friend in the United States when it Motza’ei Shabbat in Israel although it is still Shabbat in the United States because of the difference in time zones. Since the fax is being sent after Shabbat has ended in Israel and the recipient will read it only after Shabbat where he is (if one knows that his friend is G-d-fearing), this is perfectly permissible.
Summary: One need not turn off one’s fax machine or other machines before the onset of Shabbat. This is especially true in a place where most of the population is non-Jewish. Even in a place where most people are Jewish, there is nevertheless no obligation to turn off one’s fax machine according to the letter of the law. Even so, one who acts stringently by not reading the received faxes so as not to derive benefit from another Jew’s Shabbat desecration is especially praiseworthy.
In the following Halacha we shall discuss the law regarding snack machines and websites which sell merchandise on Shabbat.