Dose of Halacha

Question: Am I allowed to open post that arrives on Shabbos? Answer:   The Shulchan Aruch (OC 314:1) writes that one may crack open a barrel on Shabbos to get to the food inside. While the Mishna Berura (314:25) allows opening a container to access the food inside, he writes (340:41; Biur Halacha 340:14) that one mustn’t open a sealed letter on Shabbos as the envelope becomes a usable kli , though one may ask a non-Jewish person to do so if absolutely necessary. R’ Moshe Feinstein (Igros Moshe OC 5:21:5) also forbids opening post nowadays, writing that with modern day communication, it’s difficult to say that regular post is so important. While one may read a personal letter, especially if it contains Shabbos related material (such as a devar Torah ), one must not read any business correspondence on Shabbos. Bills, etc. are therefore muktza , irrespective as to whether they arrived on Shabbos or before. Such post is muktza on Shabbos (Mishna Berura 307:56; Igros Moshe ibid.),...

Question: I've seen some people fold their tallis on Shabbos, while some just stuff it into their  tallis bag. What's the halacha ? Answer:  The Gemara (Shabbos 113a) teaches that folding clothing on Shabbos is only permitted if the following five conditions are met: 1) It will be worn again on Shabbos, 2) No one assists in folding it, 3) It hasn’t been washed since its last use, 4) it is white, and 5) they have no other to wear. The Shulchan Aruch (OC 302:3) adds that one may, however, fold something providing that it isn’t folded on its original crease. Nonetheless, the Mishna Berura (302:19) writes that though it is permitted even if it won’t be worn again that day, ideally one should be stringent and avoid folding it. The Aruch Hashulchan (OC 302:12) explains that there are two different reasons for the prohibition: Rambam (Shabbos 22:22) writes that folding is being mesaken , fixing the garment, while the Raavad (Shabbos 23:7) holds that folding is a  ...

Question: I learned as a child that one should only recite the beracha upon seeing lightning if they have also heard thunder. Is there any basis to this? Answer: The Gemara (Berachos 59a) teaches that there are two berachos to be recited upon seeing lightning and hearing thunder though there is a machlokes as to which beracha should be recited for each. Tosafos (Berachos 59a) write that one recites either she’kocho ugvuraso malei olam or oseh ma’ase bereishis while Raavad (Berachos 10:14) writes that one should recite both berachos. The Taz (OC 227:1) and Mishna Berura (227:5) write that the minhag is to recite she’kocho ugvuraso malei olam when hearing thunder and oseh ma’ase bereishis when seeing lightning (which better demonstrates Hashem’s might). S ome people do not recite a beracha after lightning until they hear thunder, too, though this practice is wrong, as the beracha must be recited toch kedei dibbur, within a couple of seconds (ibid. 227:12). If one sees ...