- After the sin of the spies, the Children of Israel were condemned to die in the desert rather than enter the Promised Land
- The First Temple was destroyed
- The Second Temple was destroyed
- The city of Beitar was captured
- The city of Jerusalem was plowed up
For the first two events, the Gemara brings sources from the Tanakh from which we learn that they occurred on Tisha B’Av. Dating the later events was based on a tradition of the Sages. Part of the tradition tells of how, at the time of the destruction of the second Beit HaMikdash, the Nasi Rabban Gamliel survived the decree of the Roman procurator, Turnus Rufus, who decreed that he was to be put to death.
When the search for Rabban Gamliel was underway, a certain Roman officer entered the beit midrash and announced, “ba’al ha-hotem mitbakesh, ba’al ha-hotem mitbakesh!” (literally, “the man with the nose is wanted!”). Rabban Gamliel hid, and this officer tracked him down and asked whether he would merit the World-to-Come, were he to save him. When Rabban Gamliel assured him that he would, the officer threw himself off the roof of the building and died. The Romans had a tradition that when they issued a decree and one of their advisors died, they would cancel the decree. Thus, thanks to the sacrifice of the Roman officer, Rabban Gamliel survived the destruction of the Temple.
The expression ba’al ha-hotem – “the man with the nose” – is understood by most of the rishonim to refer to the outstanding individual of the generation, just as the nose is the most prominent feature on one’s face. Another suggestion is that this is a play on words. In Latin, “the man with the nose” is Nasotus, which sounds like Nasi. By using this word-play, the officer was, in effect, warning Rabban Gamliel that he was being sought by the Romans.
Tineius Rufus was the procurator during the Bar Kokhba Rebellion, and he put down the revolution with great violence. It was he who had Rabbi Akiva killed and plowed up the area of the Temple in order to symbolize its total destruction.