The Hidden Light
Throughout history, the period of the Omer has been fraught with tragedy for the Jewish People: Some 1,900 years ago, all 24,000 students of Rabbi Akiva died during the Omer because they failed to give each other enough respect. Exactly 900 years ago, whole Jewish communities were obliterated in Germany during the First Crusade. Men, women and children were slaughtered, and Torah scholars burned alive. 350 years ago, Ukrainian peasants under the leadership of a petty aristocrat called Bogdan Chmielnicki (y"s), aided by Dneiper Cossacks and Tartars from the Crimea unleashed a terrible massacre: In the synagogue in Nemirov, the Cossacks used ritual knives to slaughter the inhabitants. In this town alone, 6,000 men, women and children were butchered.
In remembrance of Rabbi Akiva's students and the other tragedies, it is the custom to abstain from things that bring joy to the heart: Weddings are not held; We refrain from cutting our hair as is the custom of a mourner.
But why do we light bonfires on the 33rd day of the Omer?
When all 24,000 of Rabbi Akiva's students had died, the world was desolate. The Torah had been forgotten - there were no pupils to go out and teach and disseminate the light of Torah. Rabbi Akiva traveled to the rabbis of the South to teach them. On Lag B'Omer, he started instructing these, his last five disciples. And from that day, the world began to brighten from these five points of light. To commemorate this event, in the Land of Israel we light bonfires to symbolize the great light that the Torah represents.
One of those last five disciples of Rabbi Akiva was the great
Talmudic sage Rabbi Shimon Bar Yochai. His departure from this
world also occurred on Lag B'Omer. On the day of Rabbi Shimon's
passing, a great light was revealed to his students when he uncovered
many of the hidden secrets of the Torah. This was written down
in the Zohar (lit. 'shining'). The bonfires symbolize the
light of the hidden wisdom that Rabbi Shimon bar Yochai revealed
on Lag B'Omer.
Sefer HaToda'ah - Rabbi Eliyahu Kitov translated by Rabbi Nachman Bulman, Simchas Yitzhak, Kol Arieh in Chagim u'Zmanim - Lag B'Omer, Ein Tov of the Chidah, Paul Johnson - A History of the Jews