When does Shabbat start?: Difference between revisions

* However, the Mishna Brurah 271:22 quotes the Rosh who argues that a certain amount of time is needed. Biur Halacha D"H Ayzo Zman posits that this period of time should be no longer than 3/4 of a mil (which is 13.5 minutes). The Mishna Brurah 271:23 concludes that in order to fulfill the mitzvah of Tofeset Shabbat (adding onto Shabbat) one should refrain from work from the time that the sun is seen at the top of the trees, or to be strict 30 or 20 minutes before Shekiyah. [Mishna Brurah (Shaar HaTzion 261:21) explains that by refraining from melacha 20 minutes before sunset one will have satisfied the opinion of the Yerayim to consider the mil to be 24 minutes and 3/4 of a mil is 18 minutes.] 39 Melachos (Rabbi Ribiat, vol 1, pg 145) writes that it's not practical to rely upon the method of determining the beginning of Shabbat by looking at when the sun hits the tree tops but rather one should rely upon times printed on calendars made by halachic experts. </ref>

# The minhag of yerushalim is to add 45 minutes to Shabbat. However, women don't need to abide by this minhag. <ref> Shemirat Shabbat KeHilchata chap 46 note 20. </ref>

# Some hold that in order to fulfill the mitzvah of adding from the weekday to Shabbat one doesn't need to make any verbal declaration, while others hold that one should verbally accept Shabbat. <ref>  

* Mishna Brurah 261:21 based on Rama 608:3 holds that a verbal declaration is needed and a acceptance in one's heart isn't sufficient.