7) In recent years, questions have been raised on the halachic status of microwave cooking. With microwave cooking, energy waves (i.e. microwaves) are generated that cause a molecular movement in the food substance. This movement causes friction between the molecules and in effect causes the food to heat itself. Because no form of “fire” is present in the cooking, there is reason to inquire whether microwave cooking is permitted.
Regarding Shabbos– With regard to hilchos Shabbos, the poskim debate whether cooking with a microwave is a biblical form of cooking or is it merely rabbinic. According to Harav Shlomo Zalman Auerbach zt”l (SS”K 1:127) microwave cooking is not biblically prohibited, while Harav Moshe Feinstein zt”l (Igros Moshe 3:52) rules that since microwave cooking is a common form of cooking, it is biblically forbidden.
Stringent– Harav Noach Isaac Oelbaum shlit”a (Minchas Chein vol. 1 page 177) discusses the use of microwaves with regard to bishul akum and he explains that according to Harav Moshe zt”l food cooked by a non-Jew in a microwave oven is considered bishul akum.16 A strict view was also expressed by Harav Shmuel Wosner zt”l (Shevet Halevi 8:185), Harav Shraga Feivish Schneebalg zt”l (Shraga Hameir 6:52:3) and Harav Yosef Shalom Elyashiv zt”l (Shvus Yitzchak vol. 6 page 61). In the OU Kosher Halacha Yomis series on Feb. 10, 2016 it states: “Although contemporary poskim differ on this question, the OU is not matir bishul akum through microwaves. Rabbi Genack once discussed this shailah with Rav Shlomo Zalman Auerbach, zt”l, who told him that the OU should be machmir regarding cooking with microwaves.”
Lenient– However, there were poskim who permit food cooked by a non-Jew using a microwave. The arguments for leniency are that when one cooks with a microwave he is not cooking by fire and that microwave technology was not available at the time when Chazal created the prohibition of Bishul Akum decree and thus was not included in the prohibition. A permissible view can be found in the Seforim Chelkas Binyamin (page 106), Lehoros Nasan (7:64) and Rivevos Efraim (8:111). Similarly, Harav Moshe Heinemann shlit”a, in an article on the Star-K website, writes, “Bishul akum does not apply to microwaved food. The rabbinical prohibition of bishul akum applies only to conventional cooking methods through fire (e.g., cooking, frying, roasting). Food prepared through microwaving is not included in the prohibition.”
Normativa Halacha– Harav Asher Weiss shlit”a (Minchas Asher Devarim) discusses this question and he concludes that one may rule leniently in case of great need. Likewise, Harav Oelbaum shlit”a discusses this issue at length and he concludes, “The poskim debate whether food cooked in a microwave is subject to the laws of bishul akum. While one should initially (l’chatchila) rule stringently, b’dieved one may be lenient.”
1) One has an obligation to honor and fear his parents. Including in the halachos of fearing one’s parents is the halacha that one may not sit in his parent’s seat. This is referring to the seat where the father davens in shul, the seat where he sits at home and the seat he occupies in his place of business. (See Kiddushin 31a, Ein Yaakov ibid, Tur, Shulchan Aruch Y.D. 240:2 and Aruch Hashulchan 240:9) The reason for this law is that when one sits in his parent’s place he thereby gives the impression that he views himself as equal in importance to his parents. (Levush)
2) This law applies to the mother’s seat as well. Meaning if a mother has a set seat in one’s home or in shul or in her place of business, the child may not sit there. (Aruch Hashulchan 240:9 and Yalkut Yosef Kibud Av V’Em page 337)
3) According to the Ohr Hachaim Hakadosh (Rishon Litzion Y.D. 240:3) one must refrain from occupying his parent’s place only when the parent is present or if other people are present, but in private one may sit in his parent’s seat. This is also the view of Harav Ovadia Hadaye zt”l (Yaskil Avdi 7 Y.D. 21:8) However, the Taz (240:3) and the Aruch Hashulchan (240:9), maintain that one may not sit in one’s father’s designated seat even when the father is not home. The Ben Ish Chai (Shoftim 2) rules that since this question concerns a Biblical commandment one should follow the more stringent view. This is also the view of Harav Yitzchak Yosef shlit”a in Yalkut Yosef (Kibud Av V’em page 338).
4) If one’s father has a special chair that he occupies which is distinct from all other chairs in the house, one may not sit on that chair even if it is moved from its permanent place. (Opinions of Rav Elyashiv zt”l and Harav Ben Tzion Abba Shaul zt”l cited in Mora Horim V’Kibbudim and Pesakim Uteshuvos page 37)
5) One may stand in the place where his father sits at home. (Shach 240:1)
6) Therefore, one may stand on his father’s chair in order to reach something on a high shelf. (Pesakim Uteshuvos page 37)
7) If the parent grants permission to the child, he may occupy his place. (Aruch Hashulchan 240:9)
8) Even if one’s parents grant him permission to sit in their seat, if he refrains from sitting there he fulfills a mitzvah. (Based upon teaching of Radvaz 1:524, and Rav Akiva Eiger zt”l 240:19)
9) The prohibition to sit in one’s parents’ seat applies only during their lifetime. One is permitted to occupy their place after they pass away. (Az Nidberu 8:60 and Tzitz Eliezer 15:41:2) [There were those that refrained from sitting in the father’s seat in shul during the year of mourning. For normative halacha, a rav should be consulted.]
10) Some even add that it is an honor for the soul of the father for his son to sit in his seat after he passes away. (See Yalkut Yosef page 353)