The gemara says, "just as when Av arrives, we
lessen our joy, when Adar comes,
we increase our joy" (Ta'anis 29.).
We understand why we must lessen
our joy in Av, since these are the
days that the Beis HaMikdash was
destroyed, but why should we
increase our joy in Adar.
The Meor Einayim asks this
question:"When Adar begins, we
increase joy. But why? The miracle
[of Purim] happened on the 14th and
15th of Adar, so why should we be
happy starting from the beginning of
the month?"
The Meor Einayim answers, "The
names of the months have meaning...
The translation of א-דר the
Alef dwells. The Alef is the Alufo
Shel Olam (Master of the World)… דר means that Hashem dwells
with people and His Shechinah
resides in this world…"
So the joy of Adar is that Hashem's
Presence resides, and is perceived,
in the world. The parashah that is
read on Shabbos is related to the
time of year it is read. Parashas
Terumah is read in the month of
Adar, because their themes are
similar. Terumah teaches us how to
build the Mishkan. The purpose of
the Mishkan was so Hashem can
dwell among us. As the passuk
states, "Build
me a sanctuary, and I will dwell
among them" (25:8). Adar is also a דירה, Hashem's dwelling among us.
Now we understand why the gemara
contrasts (and compares) Adar to
Av, as it says, "Just as when Av
comes, we lessen our joy, when
Adar comes, we increase joy." Why
is Av mentioned? It could have
simply said, "When Adar comes, we
increase joy." The answer is the
gemara is showing us that the joy of
Adar is the exact opposite of the
mourning in Av. In Av we mourn
the destruction of the Beis
HaMikdash, and in Adar we rejoice
with building the Mishkan, the דירה,
Hashem's presence in the world.
