Today is the 10th day of the month of Tevet on the Jewish calendar.
Today, Jews around the world will be fasting from sunrise till after sunset.
Why do we fast on the 10th day of the month of Tevet?
On the 10th of Tevet started the siege on the Jerusalem, a siege that ended with the destruction of the first Temple, some 2500 years ago. The fast on the 10th of Tevet is a form of mourning; we still are mourning the destruction of the Temple, we still are living the pain.
Why are we still mourning an event that happened 2,500 years ago?
Why live in the past? Why not enjoy the present and focus on the future?
Well, the Temple wasn't just a building. The Temple was a concept, a way of life, a flagship.
The Temple in Jerusalem was the world's spiritual center. People from all over the world - Jews and non Jews - came to Jerusalem to get inspired, to absorb, to re-calibrate.
The rituals and the atmosphere at the Temple inspired people; people used to come to the Temple to receive guidance how to live properly, how to lead a meaningful life. The Temple in Jerusalem was the representation of man kind's advantage over all creatures: spirituality, morals, behavior.
After visiting the Temple, people had a better understanding of our responsibility as human beings to live a spiritual life, develop the world and live in peace and harmony.
The destruction of the Temple ended an era - for the whole world in general, for the Jewish people in particular. The center for Jewish spiritual life was gone. No gathering together. No rituals. No place to celebrate the holidays or practice our religion. The Jewish Supreme Court as well as other major offices/committees - those were all gone and the people lost guidance.
We mourn on the 10th of Tevet in order to remember and internalize the ramifications of ill doings.
If we don't remember the past, we won't be able to appreciate the present.
We remember the past and its glory in order to plan and create a much better future.