Wednesday, March 04, 2015

For the record: My shittah on Ta'aniyos D'Rabbanan

On the off-chance that someone cares :-) ...

According to my best understandings of the issues,

if you go to you will find many zmanim.

A Rabbinic fast, I believe, should be commenced at the zman of 72 minutes as 16.1 degrees (not 72 fixed minutes) and may be concluded at the zman identified as that of Rabbi [Yechiel Michel] Tukaccinsky (27 minutes as degrees), or for one having difficulties, at the zman identified as that of Rabbi Schneur Zalman of Liadai, the Ba'al HaTanya (24 minutes as degrees - which, according to Rabbi Dr. Yehuda (Leo) Levi is 5.95 degrees).


  1. What is your reasoning here? Why use degrees as opposed to fixed minutes? How do you decide which opinion? Did you just pick most lenient? Today when there is ein milchamah v'ein shalom, is the obligation to fast lessened?

  2. I seem to recall that tzeis is shlosha kochavim beinonim, but by shabbos, because of chumra of deoraisa, we use kochavim ktanim, in case we can't recognize which are true beinonim. It follows that there should be a different zman for drabanans. But most shul calendars don't differentiate, and use shabbos zman (albeit not Rabbeinu Tam, though, for those who keep it). Perhaps this is your reasoning. But for krias shema of arvis which is also deoraisa, Kaluach allows various choices all of which are less than the shabbos zman, including a 24 minute zman perhaps from Baal Hatanya. So please explain.