Rabbi Aharon Berachia ben Moshe of Modina (? - 1639) was an Italian Kabbalist and a student of Rabbi Menachem Azariah of Fano. At the request of the Burial Society at Mantua, he instituted rites for them. The author of many Kabbalistic works, he is perhaps best known for his work Ma'abar Yabbok, which contains mystical dissertations on purity and holiness. He also wrote additional prayers to be offered for the sick and the dead, as well as a code of conduct for their treatment. Many of the prayers recited at the gravesites of the deceased were composed by him.
Tradition has it that an angel called a "maggid" would come and study with him, similar to the angel that would visit Rabbi Yosef Caro.
During the Three Weeks, from 17th of Tamuz to the 9th of Av, we commemorate the conquest of Jerusalem, the destruction of the Holy Temple and the dispersion of the Jewish people.
Weddings and other joyful events are not held during this period; like mourners, we do not cut our hair, and various pleasurable activities are limited or proscribed. (The particular mourning customs vary from community to community, so consult a competent halachic authority for details.)
Citing the verse (Isaiah 1:27) "Zion shall be redeemed with mishpat [Torah] and its returnees with tzedakah," the Rebbe urged that we increase in Torah study (particularly the study of the laws of the Holy Temple) and charity during this period.
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The Three Weeks
It all began with an unbounded light
that filled all and left no room for a world to be.
Then that light was withheld
so that the world might be created in the resulting void.
Then the world was created,
with the purpose of returning to that original state of light
—yet to remain a world.
That is something greater than unbounded light:
A dark world that shines, through our hard work.