Yahrtzeit Riddle Solved

לז"נ אבי מורי  ר' צבי יהודה בן ר' משה  זללה"ה

נפטר ל' כסליו א' דר"ח טבת                  

Yakov died leaving behind two sons, Reuvain & Shimon They both live in ט

the same city yet, Revain keeps the Yahrzeit one day before Shimon.

                       HALACHA V'LO  LEMA'ASEH

The year  Yakov died , had two days Rosh Chodesh . He died on the first day

Rosh Chodesh Teves (30 Kislev)

The following year ( first yahrzeit)   There was only one day Rosh Chodesh (no

30^th kislev)

There is a machlokes haposkim* which day to keep  the yahrzeit since

there is no 30th Kislev.

The Mogen Avraham (#568) holds you  keep  the  yahrzeit  on the 29^th of kislev

which is last day of the month.   Once he keeps the 29th as the first

yahrzeit, he must continue for the rest of his life on the 29^th of kislev.

(when it is a Chodesh Choser)

The Shaarei Teshuva ,Bigdei Yesha and Aruch Hashulchan, hold you always

keep the Yahrzeit on Rosh Chodesh.

The first year after Yakov’s  death , Reuvain davened in  BHM”D Chofetz Chaim.

He asked his Rov when to keep the yarzeit .

His rov said,  The Mishna Veruro , writes (568 sk 42) that the minhag is 

like the Mogen Avraham. Therefore being

this year there is only one day Rosh Chodesh, he has to keep the yahrzeit

on the 29^th of Kislev. 

The Magen Avraham writes the first yahrzeit establishes all the coming yahrzeits.

He  must also continue to do so all the years, (whenever there is one day Rosh Chodesh)

Shimon davened in Tiferes Yerushalayim and asked  his Rov when to keep

the Yahrzeit. His Rov answered that R. Moishe  In Igros Moshe (Y.D. 3-159)   argues 

on the Magen Avraham and paskens like the Aruch Hashulchan etc.

therefore he should keep the Yahrzeit   on Rosh Chodesh  Teves.

Since Reuvain started the first time he had yahrzeit on a Chodesh Choser on 

the 29^th of kislev He must continue whenever there is a Chodesh Choser for 

the rest of his life the 29^th.

Shimon started the first yahrzeit on Rosh Chodesh , he must continue on

Rosh Chodesh. (no one argues on  the magen avraham,  that the first

yahrzeit establishes the date forever.) 

Hence two different days Yahrzeit for one person.

* There are two more shitos 1) Taz   2) Elef Lamateh