The two Batei Mikdosh were destroyed because of aveiros, but the aveiros of these two eras weren't the same. The primary aveiros of the first Beis HaMikdosh were avodah zarah, giluy arayos, and shefichus damim. The second Beis HaMikdosh was destroyed because of sinas chinom [baseless hatred].
There were other differences between the aveiros of these two eras.
The Gemara (Yoma 9) states that one of the differences is that “the first Beis HaMikdosh, their aveiros were revealed, and therefore, the date when the galus would end was revealed to them. In the second Beis HaMikdosh, their sins weren't revealed, and therefore, the end of the galus was not revealed.”
Rashi explains that by the first Beis HaMikdosh, people were transparent; they didn't conceal their true selves. Everyone knew who was a tzaddik and who was a rasha. They were revealed, therefore, it was revealed to them that after seventy years, they would return to Eretz Yisroel (see Yirmiyahu 29:10). But by the second Beis HaMikdosh, not everyone was transparent. There were resha'im who pretended to be tzaddikim. No one knew who was a true tzaddik and who wasn’t. They were concealed. Therefore, the end of the galus was hidden from them. They weren’t told when Moshiach would come.
Rebbe Yohonoson Eibshitz zt”l (Ya’aras Devash 7) explains the Gemara in another way. He explains that “during the first Beis HaMikdosh, their sins were revealed," means the navi told them the reason for the exile. The pasukim in navi reveal that they were being punished for avodah zarah, giluy arayos, and shefichus damim. They knew what their sins were, so they knew how to improve. Therefore, it didn't take them long to improve their ways. Seventy years later, they returned to Eretz Yisroel.
But their sins weren’t revealed during the second Beis HaMikdosh. There were no nevi'im in that era to tell them the cause of their punishment. Although the chachomim told them that the destruction was caused by sinas chinam, it was hard for people to accept that because sinas chinam doesn't appear to be a severe aveirah. They didn’t know the reason for their punishment, so it was harder for them to do teshuvah. It is still hard for us to recognize the severity of sinas chinam, which is why nearly two thousand years have passed, and we haven’t been redeemed.
The Arizal created a hesger, an exclusive compound for his ten primary students, where he taught them the secrets of the Torah. He warned them to avoid machlokes.
But one Friday, two women got into a fight about some matter, and their husbands got involved. Their shouts could be heard from the distance.
Before Shabbos, the Arizal with his students walked out of Tzfas to be mekabel Shabbos in the fields (as this was their weekly custom). The Arizal was usually extremely happy at this time, but this week, he appeared sad. Reb Chaim Vital zt”l asked him about this, and the Arizal replied, “I heard the samach mem (Satan) say, גם אתם גם מלככם תספו – “Also you and your king will die” (Shmuel 12:25), and I understand this to mean that I am going to die together with some of my students. And it's all because of the machlokes that occurred today. As long as there was peace among you, the Satan couldn't enter our secluded compound.” And that is what happened. Less than a week later, on the fifth of Av, the Arizal and five of five of his students were niftar.
The Shulchan Aruch (554:20) states,אין שאלת שלום לחבירו בתשעה באב - “One mustn't greet his friend on Tisha B'Av.” But why not? The Beis HaMikdosh was destroyed because of sinas chinom. It would seem that Tisha B'Av is the ideal time to greet one’s fellow man, to increase love and peace.
The answer lies in a Gemara which was recently learnt by Daf HaYomi, the Gemara in Gittin (58a) says: “There was an apprenticed carpenter whose eyes desired his employer's wife. Once, the carpenter needed a loan. The apprentice said, ‘Send your wife to me, and I will give her the money.’
The apprentice detained her in his home for three days. The carpenter came and asked, “Where is my wife?” “I gave her the money and sent her back right away. But I heard that some youth defiled her on the way.” “What should I do?” “I suggest you divorce her.” “But her kesubah is very large, and it will cost me a lot of money to divorce her.” “I'll lend you the money.” The carpenter divorced his wife, and the apprentice married her. When the loan was due, the carpenter could not pay his debt, so the apprentice said, ‘Work for me, and you will pay off your debt with your work.’ “The apprentice and his new wife ate while the carpenter served them. As he poured them drinks, his tears fell into their cups. That is when the decree for the destruction of the Beis HaMikdosh was sealed in heaven.”
The Ya’avatz notes that the apprentice didn’t transgress an aveirah because he married the carpenter's wife after she was divorced. Yet, because of his deeds, the Beis HaMikdosh was destroyed. “From this, we learn that there are aveiros that aren’t written explicitly, yet they are extremely grave and despised by Hashem. They are worse than the cardinal sins.”
This is an important concept to keep in mind. There is the spirit of the Torah, the concepts of good and bad, and sometimes these details aren’t explicitly spelled out in the Torah. However, the heart of a Yid understands the severity of such matters.
An example of this concept is the Gemara (Bava Metzia 30b), that states, “Yerusholayim was destroyed because they ruled by the laws of the Torah.”
The Gemara asks, “Which laws should they follow, if not the laws of the Torah?” The Gemara responds, “The [problem was they] followed the laws literally and never went beyond the letter of the law.” They failed to consider the spirit of the law as well. They only focused on what is explicitly prohibited or permitted, and that isn't sufficient.
Now, let’s return to our question. We want peace on Tisha B'Av, so why don't we greet people on Tisha B’Av? The answer is that Tisha B'Av, we seek true peace, not lip service. Throughout the year, people smile at their fellow man and greet one another, but they don't necessarily care about them in their hearts. Tisha B'Av, we take a break from greeting our fellow man, reassess, and strive to reach a higher level. We want to go beyond the letter of the law, beyond what's commonly expected, and to develop genuine peace and love among Yidden. (R’ Elimelech Biderman)
