Normal history is about the winners, not the losers; the victors, not the victims. Tisha B’Ab memorialize’s religiously, a national historical defeat. Long before the Book of Lamentations there were pagan lamentations expressing grief about the destruction of a city like Ur. but not until almost six centuries after the second destruction of Jerusalem and its holy temple, did another religion (the Shiite Muslim community) begin its similar annual holy memorialization of the massacre of Muhammad’s grandson Husain, his family and his few followers on Ashura, the 10th day of Muharram, a fast day with many similar rules and ceremonies to Tisha (the 9th) B’Av.
Ashura (10th day of Muharram) was originally designated for Muslims by Muhammad in the summer of 622 CE, soon after being forced to flee from Makka, as a day of fasting from sunset to sunset, similar to the Jewish Day of fasting: Tisha B’Av (which in that year, like this year, was observed on the 10th because it fell on Shabbat, when Jews are forbidden to fast).
According to Sahih Bukhari – Hadith: 261 Volume: 6 Book Subject: Prophetic Commentary on the Qur’an, Ibn Abbas narrated that the Ashura Fast was being observed by Medina’s Jews when Prophet Muhammad arrived in Medina and he ordered Moslems to adopt that fast: “When Allah’s Apostle arrived at Medina, he found the Jews observing the fast on the day of ‘Ashura’ (10th of Muharram). The Prophet asked them (about it) and they replied, “This is the day when Moses became victorious over Pharaoh.” The Prophet said (to the Muslims), “We are nearer to Moses (because we are being oppressed now) than they, so fast on this day.”
Six years from now, in the year 2022, the Muslim fast of Ashura (Muhharam 10th) will again coincide with the Jewish fast of Tisha b’Av (Av 9th) as it did 1400 solar years previously in 622 CE, the year Muhammad escaped from Makka and settled in Medina. The two dates will overlap because many Muslim scholars say that the 9th or the 11th of Muhharam should also be observed, and the Rabbis say if Av 9th falls on Shabbat, as it does this year, it should be observed on Av 10th.
In addition, Rabbi Yohanan ben Zakki, who escaped from the besieged city of Jerusalem shortly before it was captured by the Romans in 70 CE says that mourning over the destruction of Jerusalem and its Holy Temple should be observed on Av 10th because, while the Temple was set on fire on the 9th, it was not totally destroyed until the 10th.
Why did the Jews of Medina tell Muhammad: “This is the day when Moses became victorious over Pharaoh.”?
Because Medina’s Jews knew the tradition that the Jewish Messiah was/will be born on Tisha B’Av. This rabbinic midrash teaches us that very good things like monotheism can, with God’s help, grow out of very bad things, like the many years of Muhammad’s rejection and persecution by the polytheistic, idol worshipping Arabs in his home town of Makka.
Just as Moses overcame Pharaoh after a decade of plagues; so too would Muhammad overcome his hometown enemies in Makka.