No. I believe we should abolish the practice of fasting to commemorate the destruction of the Jerusalem Temple on the ninth day of the month of Av, known as Tisha B'Av.Now before you convene a synod to excommunicate me, know that I am in good company. In the third century CE the greatest Tanna, Rabbi Judah the Prince, tried to abolish Tisha B'Av.
My son Yitz called my attention to this passage below which records the rabbi's action [Soncino Babylonian Talmud (2012-04-25). Megillah and Shekalim (Kindle Locations 739-743). Kindle Edition.] and to Tosafot's glosses (at Megillah 5b) which reject the premise that someone could entertain the notion of abolishing Tisha B'Av.
R. Eleazar said in the name of R. Hanina: Rabbi planted a shoot on Purim, and bathed in the [bathhouse of the] marketplace of Sepphoris on the seventeenth of Tammuz and sought to abolish the fast of the ninth of Ab, but his colleagues would not consent. R. Abba b. Zabda ventured to remark: Rabbi, this was not the case. What happened was that the fast of Ab [on that year] fell on Sabbath, and they postponed it till after Sabbath, and he said to them, Since it has been postponed, let it be postponed altogether, but the Sages would not agree.Of course, if Rabbi Judah the Prince (compiler of the Mishnah) once tried to abolish Tisha B'Av but the sages would not agree to it, I do not expect that the sages of our times will agree with me to abolish Tisha B'Av.
Yet here is why they should.
I concur that as a culture we need to remember the calamities of the past so that we can be vigilant and prevent the calamities of the future. But we need effective ritual memories that are clear and unequivocal. Tisha B'Av commemorates that the city of Jerusalem and the Temple in it were destroyed.
Because the city has been rebuilt in modern Israel, this befogs the symbolism of the past destruction and renders it less effective.
I have been mulling over this issue for thirty years or more. In 2012 I mused as follows (with a few edits added).
Is Tisha B'Av relevant? No I do not think that the fast of Tisha B'Av is relevant anymore. I need a holiday from Tisha B'Av.
That day was for a long time a commemoration through fasting and prayer over the destroyed city of Jerusalem and the Temple. I visited Jerusalem in May of 2011 (ed.: and again in 2013, and many more times since then) and can attest that the city is not desolate. It is without reservations, glorious.
Who then wants the bleak story to be told? Archetypally the militant "celebrity" archetype wants to keep recalling defeat, destruction and desolation, to spur team Jews on to fight the foes and to triumph at the end of time. That scheme may work for that archetype as long as the facts of reality do not fly smack in the face of the narrative. And when they do, what then? The narrative loses its force. It becomes absurd.
I cannot imagine Jerusalem in ruins. Period. And indeed, why should I perpetuate an incendiary story of gloom and doom into a diametrically opposite positive world of building and creativity? The era of desolation has ended.
For over twenty-five years, I've been lamenting the irony of lamenting over a city that is rebuilt. It's more rebuilt now -- way more -- than it was twenty five plus years ago. What do I do then about Tisha B'Av, the Jewish fast day of lament and mourning? Here is what I said those many years ago.
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In our view, it's a perfect opportunity for Jewish leaders to show that they can be lights unto the nations, i.e., examples of high moral behavior that will redound to the culture at large.
When we translate our ideas to the print medium, the output gets longer, gets edited and gets read by different readers. Here's our guest column from our local Jewish newspaper of record, the Jewish Standard.