The Gemorah Menachos 65b says
וספרתם לכם tells
us that every individual must count.
Tosfos explain that we would have thought there is an obligation only on
בית דין
like the counting of the years of
shmittah,
קמ"ל there is an obligation
on every individual.
Why would we have
thought there is only an obligation on the
בית דין if it is a mitzvah
like any other?
The Chizkuni in Behar says
that in regard to
shmittah the Torah mentions the counting once and its
merely an obligation on the
בית
דין.
Siferas Haomer is
mentioned in Reah and in Emor to tell us there is an obligation on the
בית דין
and an obligation on the individual.
He
holds even at the end of the day there remains an element of obligation on the
בית דין
alone.
What is the nature of this
obligation?
In regard to the counting of the shmittah cycle Reb
Chaim explains that the mitzvah isn’t merely to count but that it is the count
of the cycle that gives the kedusha to the year of yovel. The Torah calls the holiday Shavout
indicating that it is the חפצא
of the counted weeks that give the kedusha to the holiday. Therefore, we would have said (and according
to Chikuni we do say,) that the counting is part of establishing the holiday
and has to be done by בית
דין just as they are entrusted with being מקדש the months.
Based upon this idea we can understand the Gemorah in
Menachot 66a that Amemar counted the days but not the weeks because it is a
mere זכר למקדש. It is צ"ע why not count the weeks as well because of
זכר למקדש? However, in light of the Chizkuni it is beautiful
for the counting of the weeks is mentioned in Reah where it says וספרת לך meaning to ב"ד
that they must count the weeks. It is in
Emor where the Torah says to count the days and it says וספרתם לכם, an obligation on
every individual. Therefore, the mitzvah
onב"ד is the weeks so there is no זכר למקדש for the individual to
do it, is it only the mitzvah to count the days that there is זכר למקדש for every individual (Eretz Hatzvi (Shecter) siman 3 and footnote 3, see also Bad
Kodesh on Moadim.)