Dose of Halacha

Shiurim in CC (ml) Chazon Ish R’ Moshe Feinstein R’ Avraham Chaim Naeh Larger Size Smaller Size Revi’is 145 130.6 85.8 86 Kezayis 50 43.5 32.5 27 There is a lot of debate amongst the Rishonim and later Poskim as to how to accurately calculate the shiurim (size or volume) of halachic measurements. The Shaarei Teshuva (OC 486) and Mishnah Berura (486:1) rule that we should be particularly stringent for mitzvos that are deoraisa . R’ Moshe Feinstein (quoted by R’ Avrohom Blumenkrantz) held, therefore, that one should follow the larger shiur (above) for the mitzvos that are  deoraisa , and rely on the smaller shiur for those that are derabanan. A healthy person should certainly try to follow the Chazon Ish’s s hiurim for the first kezayis of matza and the afikoman to be sure of fulfilling the mitzva according to all opinions . This is estimated at about 2/3 of a Mach...

Question: Is one allowed to shave on chol hamoed ? Answer: The Mishna teaches that chazal instituted that one must not take a haircut on chol hamoed to ensure that one does so before Yom Tov. Thus, Rambam (Yom Tov 7:17) and the Shulchan Aruch (OC 531:2) write that one must not take a haircut on chol hamoed even if one took a haircut beforehand. Only one who was unable to do so due to being imprisoned, etc. would be permitted to do so now. The Tur (OC 531:1) quotes Rabbeinu Tam who writes that since the Mishna’s reason for the prohibition is to ensure that people will take a haircut before Yom Tov, if one did in fact have a haircut beforehand, they may do so again on chol hamoed . Nonetheless, the Tur explains why other rishonim disagree. Firstly, the Gemara does not make any such exception. Additionally, others will not know that he shaved before Yom Tov. The Noda Biyehuda ( OC 1:13 ; 2:99-101) wrote that it is permissible to employ a barber on chol hamoed if they were des...

Question: I don’t like wine and matza. Can I drink grape juice and eat non-wheat matza instead on Seder night? Answer: R’ David Feinstein writes that his father, R’ Moshe Feinstein held that one should push oneself to drink wine, even if it causes him mild discomfort. R’ Zvi Pesach Frank (Mikraei Kodesh, Pesach 2:35) argues that a non-alcoholic beverage does not make one happy in the same way that wine does and therefore cannot be used on Seder night. R’ Shlomo Zalman Auerbach, however, (Halichos Shlomo, Pesach 9:11) writes that grape juice has the same status as wine, as drinking grape juice also symbolises freedom. If possible, one should at least dilute the grape juice with a little wine. (R’ Moshe Sternbuch, Teshuvos Vehanhagos, 2:243) R’ Avrohom Blumenkrantz (Chasdei Avrohom 20) writes that one shouldn't use grape juice made from concentrate for kiddush or on Seder night. The Rema (OC 453:1) writes that we are accustomed to only eating wheat matza . Therefore, no...

Question: Can I play with Lego on Shabbos? Answer: The Shulchan Aruch (OC 313:6; 341:1) writes that the Torah prohibition of binyan , building, does not apply to keilim, movable items, unless the connections are particularly robust. Thus, a cup that comes apart can be dismantled and reassembled on Shabbos. The Taz (313:7) and Magen Avraham (313:12) add that there is no issur of boneh to open and close something that is designed to be regularly opened and closed. R’ Moshe Stern (Baer Moshe 6:25) and R’ Benzion Abba Shaul (Ohr Letzion 2:42:5) write that while adults should avoid playing with Lego, there is no specific prohibition in it and children can even build a model that will last some time. Many acharonim including the Chasam Sofer (OC 72) write that temporary building does not constitute binyan . Following this, R’ Ovadia Yosef (Yabia Omer OC 7:39; Yechave Daas 2:55) writes that one should be able to play with Lego on Shabbos, especially if one is playing rather than...

Question: Can we use baby wipes on Shabbos? Answer:  Squeezing a wet sponge on Shabbos is forbidden because of   sechita.   There is a lot of debate as to whether this poses a problem for using baby wipes, too. R' Yitzchak Yaakov Weiss (Minchas Yitzchak 10:25) forbids using baby wipes. Likewise, R' Pesach Eliyahu Falk maintains that as the very purpose of baby wipes is to squeeze out liquid for a constructive purpose, one cannot claim that one isn’t transgressing on   sechita . Some recommend only using wetter wipes, as the liquid is less absorbed and won’t need to be squeezed out (See The 39 Melochos, Ribiat, p352), while others only permit the drier wipes. R' Yechezkel Roth gave a hechsher to a brand that manufactured their wipes from man-made materials, such as polyester, as opposed to cotton ( gidulei karka ) which would be more problematic. R'  Yehoshua  Neuwirth   (Shemiras Shabbos Kehilchasa 14:33, note 94) quotes R' Shlomo Zalman Auer...