3) A NEDER FOR "A DAY"
QUESTION: The Gemara asks whether a Neder made to prohibit wine for "a day" ("Yom") is like a Neder made for "this day" ("ha'Yom") and is prohibited only until nightfall, or whether it is like a Neder made for "one day" ("Yom Echad") and is prohibited for a period of twenty-four hours.
I would have thought that the use of YOM - generic - could indicate rosh hashana which is called The yom - Hayom
thank you for all your efforts
efraim goldstein, NY usa
I assume that you are referring to the Zohar (Bamidbar p. 231 cited by the Taz in OC 597:1) who writes that whenever the verse says "Vayehi ha'Yom" it refers to Rosh Hashanah.
First of all, that only refers to verses with the full expression "Vayehi ha'Yom" (reminiscent of the "Vayehi Erev Vayehi Voker" of creation). Aside from that, Nedarim are judged by Lashon Bnei Adam (Nedarim 49a) and do not follow the same rules as scripture.
Kollel Iyun Hadaf