Dose of Halacha

Question: Can one use a doorknocker on Shabbos? Answer: The Gemara (Beitza 36b) writes that chazal forbade one from dancing and playing with musical instruments on Shabbos as they were worried that they may come to fix a broken instrument ( makeh bepatish ). Thus, the Gemara (Eruvin 104a) discusses whether one may make sounds that have no melody such as knocking on a door. Based on this, Rambam (Shabbos 23:4) and the Beis Yosef (OC 338:1) write that one mustn’t use any instrument that makes noise as we are concerned that one will use it to play music. The Mishna Berura (338:1) writes that the same applies to objects that aren’t created for noise. Thus, one should even avoid clapping in the normal way. The Biur Halacha (338:1) quotes Rambam (Pirush Hamishnayos, Eruvin 104a) who implies that one may use a door knocker on Shabbos. Nonetheless, the Rema (OC 338:1) writes that one must only knock on a door on Shabbos with one’s hand and not with a door knocker. R’ Yehoshua Neuwi...

Question:  Can one adjust a fan on Shabbos to blow in one direction? Answer:  R’ Moshe Feinstein (Igros Moshe OC 3:49; 4:91:5) writes that electric appliances such as lamps and fans are  muktze  as they are considered to be  kelim shemelachtam leissur,  items that serve a forbidden action on Shabbos. The Shulchan Aruch (OC 308:3) writes that such items are allowed to be moved either if one needs the space ( letzorech mekomo ) or for personal need ( letzorech gufo ). Thus, R’ Moshe Feinstein and R’ Ephraim Greenblatt (Rivevos Ephraim 1:235; 5:250; 6:206) allow one to move a fan on Shabbos so that it blows in the right direction. Similarly, one can adjust its mechanical levers to allow it or prevent it from oscillating. R’ Moshe warns, however, that one must be careful to ensure that the plug doesn’t get pulled out. Likewise, R’ Yisroel Belsky (quoted in The 39 Melochos, p1235:n165) advises that the speed dial is taped down before Shabbos to ...

Question: Can one use a disposable cup for Kiddush? Answer: The Shulchan Aruch (OC 183:3) writes that one mustn’t use a cracked cup for bentching. The Magen Avraham (OC 183:5) writes that even a broken base disqualifies the cup. The Mishna Berura ( 183:11) applies this halacha to the cup used for kiddush and havdala, too (See Shulchan Aruch OC 271:10). There is a machlokes as to how to apply this halacha to disposable cups. R’ Moshe Feinstein (Igros Moshe OC 2:75; 3:39) writes that one mustn’t use a disposable cup for kiddush as it isn’t respectable. Using a disposable cup would be worse than a real cup with a cracked base. R’ Yitzchak Yaakov Weiss (Minchas Yitzchak 10:23) adds that just as one wouldn’t tovel such a cup as it isn’t considered a proper kli, so too it doesn’t qualify as a proper kli for kiddush (See Ohr Letzion 2:47:12) . R’ Binyamin Zilber (Az Nidberu 6:48), however, writes that there is no need for the cup to be particularly respectable. If there ...

Question: I always say tefillas haderech when I travel abroad. Do I also need to say it when I travel more locally? Answer: According to the Gemara (Berachos 30a), one says tefillas haderech when travelling a parsa (approximately 2.5 miles) out of the city. As danger is more prevalent on a deserted road, the Tehila Ledovid (110:3) writes that one only says it when travelling on a road that is not within a parsa of any city. R’ Shlomo Zalman Auerbach (Halichos Shlomo, Tefilla 21:31) suggests that as there is less inherent danger in travelling nowadays, it is best to recite it without the concluding beracha , or to say it in the shemone esrei (in shema koleinu ) before travelling. R’ Chaim Pinchos Scheinberg also suggests this if one will find it easier to concentrate when not driving (Tefilla Kehilchasa 27:80). While, one travelling, from Manchester to London, for example, should recite it, there are different opinions about one travelling on a shorter journey, such as from...

Question: Should I say borei nefashos after drinking a coffee? Answer: The Shulchan Aruch (OC 210:1) writes that one doesn’t say borei nefashos after drinking unless they drink a revi’is in one go (See Mishna Berura 210:1). The Baer Heitev (204:12) quotes some poskim who hold that one should recite borei nefashos after sipping a hot drink. The Shearim Metzuyanim Behalacha (51:5) compares this to drinking alcohol, which according to the Taz (OC 210:1), one would say borei nefashos after drinking just a shot as that is the normal way of drinking it (See Har Tzvi OC 1:159). Nonetheless, the Aruch Hashulchan (OC 202:7) writes that even though this is the normal way of drinking hot drinks, the Shulchan Aruch doesn’t differentiate between hot and cold drinks, etc. Likewise, the Baer Heitev sides with the other poskim who disagree, saying that the minhag is not to say borei nefashos. To avoid the safek, however, he advises one to leave a revi’is in the cup to cool down t...

Question: I wanted to bake a milky bread loaf though was told that I couldn’t. Is that true and why? Answer: The Gemara (Pesachim 30a; 36a) writes that chazal instituted that one mustn’t bake a loaf of bread using milky or meaty ingredients as people may not realize and come to eat milky bread in a meaty meal, or vice versa (See Shulchan Aruch YD 97:1). The Aruch Hashulchan (YD 97:1) writes that this is so serious that if one accidentally baked such bread, one mustn’t eat it at all (See Kaf Hachaim YD 97:11; Yabia Omer YD 1:5). The Gemara writes that one may bake milky or meaty bread, however, providing that they bake it kaein tura, like the eye of an ox. According to Rashi (Pesachim 36a) this refers to baking a small quantity while Rambam (Maachalos Asuros 9:22) understands it to mean baking the bread in a different shape to regular bread. The Shulchan Aruch (ibid) writes that if either of these conditions were met, one could bake such bread. Thus, in Yerushalayim , all mi...