Dose of Halacha

Question: I know that we’re not supposed to use soap bars on Shabbos but can we use liquid hand soap? Answer: The Shulchan Aruch (OC 328:22) writes that one may rub oil into a (minor) wound on Shabbos, but not fat that will melt. The Mishna Berura (328:71) adds that this applies equally to oil that has solidified. The Rema (OC 326:10) explains that one cannot use bar soap on Shabbos because it is nolad, (creating a new entity). The Mishna Berura (326:30) explains that doing so is also an issur of memachek (smoothing). R’ Moshe Feinstein (OC 1:113) writes that he didn’t allow liquid soap in his house, either, as it is also a potential issur of memachek. Nonetheless, the Aruch Hashulchan (OC 326:11) and Kaf Hachaim (OC 326:43) write that one can prepare liquid soap before Shabbos. R’ Yaakov Yechezkel Posen (Kitzur Hilchos Shabbos 32:4) writes that common practice is to be lenient like these poskim . Similarly, R’ Yosef Shalom Elyashiv ( Kovetz Teshuvos 1:38, quoted in Orchos Sha...

Question: May one use a non-electric thermometer on Shabbos? Answer: The Mishna (Beitza 28a) teaches that one mustn’t measure things on Shabbos or Yom Tov. Tosafos (Shabbos 126b) explains that doing so is uvdin dechol , mundane, weekday activity, while Rambam (Shabbos 23:12) implies that it may lead to writing (See Shulchan Aruch OC 323:1). The Shulchan Aruch (OC 306:7) writes that one may measure, however, for mitzva and health purposes (See Shabbos 157b). Thus, R’ Moshe Feinstein (Igros Moshe 1:128), R’ Yitzchak Yaakov Weiss (Minchas Yitzchak 3:142; 7:22; 10:31:8), R’ Eliezer Waldenberg (Tzitz Eliezer 3:10; 14:30), R’ Yehoshua Neuwirth (Shemiras Shabbos Kehilchasa 40:2) and R’ Ovadia Yosef (Yabia Omer OC 9:108:156; Yechave Daas 4:29 ) write that one may use a (glass) thermometer on Shabbos. There is a machlokes , however, as to whether one can use a strip thermometer which changes colour according to the temperature. R’ Neuwirth writes that R’ Shlomo Zalman Auerbach only al...

Question: I know that one isn’t supposed to touch the sefer Torah with one’s hands. Does this apply to the megilla , too? Answer: The Shulchan Aruch (OC 147:1) writes that one mustn’t touch a sefer Torah without a cloth. The Rema writes that while some extend this prohibition to other kisvei kodesh, holy writings, that isn’t our minhag. Nonetheless, he cautions that one should ideally wash one’s hands before handling them (See Beis Yosef OC 147:1). The Magen Avraham (147:1) writes that Rema was referring to printed sefarim . The Rema would agree, however, that one must wash one’s hands before touching a kosher megilla . The Elya Rabba ( 147:1 ) and Panim Meiros (1:76) however, disagree, writing that when the Rema writes that it is ideal to wash one’s hands, he was referring to writings such as the megilla which don’t contain the same kedusha as a sefer Torah. One only needs to wash one’s hands if they are dirty (See Aruch Hashulchan OC 147:5; Kaf Hachaim OC 147:5; 7). ...

Question: I walked out of our holiday home on Shabbos and realized that there were some papers in my pocket. What should I have done? Answer: Rambam (Shabbos 12:9; 13:5) writes that in order to transgress the melacha mideoraisa of hotza’a, carrying on Shabbos, one needs to have picked an item up ( akirah ), carried it into another reshus (domain) or at least four amos in a reshus harabim ( hiluch ) and have put it back down again ( hanacha ). If one finds oneself inadvertently carrying on Shabbos, one should try one’s utmost to eliminate one of these stages in order to minimize the prohibition. An area enclosed by an eruv is considered a reshus hayachid while most streets and parks would be a carmelis. Carrying from one to the other is assur miderabanan (See Shabbos 6a; Shulchan Aruch OC 346:1) . Rambam (Shabbos 13:8) writes that if one stops walking, it is considered to be hanacha . Thus, one who accidentally carried something to another domain and immediately broug...