These halachos about the start of Yom Kippur and Tosefes Yom Kippur are based on the Mishna Berura, reflecting Ashkenazi practice
Eating After Seudah Hamafsekes
- Strictly speaking, one does not accept Yom Kippur on oneself just by finishing the Seudah Hamafsekes.
- However, it would be preferable to verbally, or at least mentally say prior to bentching that one isn’t not accepting the Fast on oneself when one does so (SA 608:3, MB 12).
Tosefes Yom Kippur – Time Added on to Yom Kippur
- There is a positive Mitzva from the Torah to add on to Yom Kippur, ie to commence the fast and all its restrictions earlier than sunset. This extra time is known as ‘tosefes’ and is also observed on Shabbos and other Chagim. It is factored into the published times for the commencement of Yom Kippur, Shabbos etc.
- This is learnt from the passuk saying that the fast runs ‘from the 9th of the month in the evening,’ implying there is part of the fast that is held on the 9th. (SA 608:1, MB 1, SSK 46:1)
- How long: The Mishna Berura cites that requirement is to add on a little less than 15 minutes as ‘tosefes’ before sunset but that it is praiseworthy to add 20 to 30 minutes (for reasons we won’t elaborate here, this larger quantity of tosefes isn’t applicable on a Motzei Shabbos).
- Note that several poskim rule, and derive from a comment of the Mishna Berura, that the basic requirement is actually only around 5 minutes.
- Different communities have different customs – in Yerushalayim the custom is for candle lighting to take place 40 minutes before sunset, whereas elsewhere in Eretz Yisrael the custom is to add 20 minutes [note that men davening Mincha at shul on a regular Friday afternoon at candle lighting time, will be using a shorter time for tosefes Shabbos, normally just a few minutes, per the view mentioned above] (SA 608:1, MB 2, MB 261:22 – 23, Dirshu 28, BH”L 261:2 D”H Eizeh Zman, PT 261:6, 293:2).
How One Accepts the Fast
- Automatic: The Fast and its restrictions automatically start a few minutes before Shkiah, in line with the basic requirement of Tosefes as above.
- Verbally: However, to accept Yom Kippur earlier than this (which we customarily do), and according to some, to ensure that one actually fulfils the Mitzvah of Tosefes Yom Kippur even with the basic few minutes, one should verbally accept the Fast upon oneself (such as by saying ‘I accept upon myself [the sanctity of] Yom Kippur’; note this also applies by accepting Tosefes Shabbos and Yom Tov) (Dirshu 261:20, PT 608:1).
- Women Candle lighting: Women accept the Fast on themselves by lighting candles.
- In cases of need, however, they can mentally or verbally state beforehand that they do not wish to bring Yom Kippur in yet, so long as they do not say Shehecheyanu when they light candles but rather wait until they say it with the congregation in shul, or until she formally brings the Fast in at home.
- If they do have in mind to not yet bring in the Fast, they should accept Yom Kippur via another method outlined below (SSK 45:15).
- See our more detailed treatment of Candle Lighting for Yom Kippur here.
- Shechecheyanu: In shul, the recitation of the bracha of Shehecheyanu after Kol Nidrei is a formal acceptance of Yom Kippur.
- Verbal acceptance: However, when this is going to be said too late for the time of Tosefes Yom Kippur outlined above (which I believe is normally the case in may shuls), one should verbally accept the fast upon oneself earlier as above, in time to fulfil Tosefes Yom Kippur, though men should ensure to put their Tallis on with a bracha first.
- To this end, the text of Tefilla Zakka, commonly said before Kol Nidrei, contains a line stating that one now accepts the Fast and its restrictions upon oneself (MB 619:4, Dirshu 6)
