Chazal said: "The second Beit Hamikdash, in which people were involved in Torah study, in mitzvot, and in gemilut chasadim (kindness) – why was it destroyed? Because it contained sinat chinam (baseless hatred)" (Yoma 9b).
What is the nature of sinat chinam that existed at a time of Torah,mitzvot, and even gemilut chasadim? It appears that the hatred arose specifically through the Torah they studied and the mitzvot they performed. This period, of late Bayit Sheni, is one in which machloket(dispute) in halacha became a matter of course, starting with the major disputes of Beit Shamai and Beit Hillel. While these were disputes with proper intentions (Avot 5:17), apparently, in addition to the machloket on specific halachic issues, there was a machloket on how to go about halachic dispute.
"For three years Beit Shamai and Beit Hillel disputed, with these saying, ‘the halacha is like us’ and the other one saying, ‘the halacha is like us.’ A heavenly voice emerged, saying: ‘These and those are the words of the living G-d,’ but the halacha is like Beit Hillel’" (Eruvin 13a). The gemara explains the reason for Beit Hillel’s prominence: "They were easy going, allowed themselves to be insulted, and would mention Beit Shamai’s teachings along with and even before their own."
From the behavior of Beit Hillel, we can infer what Beit Shamai’s practice was. Chazal thereby hinted at their criticism of disputation done without patience for another’s opinion and the resulting disrespect for him. On one hand, the new situation that a broad spectrum of halachic issues was disputed is a sign that the level of Torah learning had deteriorated. On the other hand, the different rabbis had the right to decide matters according to what they believed to be true. Even if I think that another is wrong, I must respect him for doing what he believes is correct. One who fights vociferously with his counterpart or disgraces him because he has a different opinion not only does not remove the machloket but spreads it to other areas. It sharpens themachloket until it creates not only different opinions but different camps. This is the sinat chinam that caused the Beit Hamikdash’s destruction.
Such opposing philosophies can exist at any time, most certainly in ours. The Religious Zionist camp and those who claim to have only Torah differ as to understanding the events of our time. While the disagreement could be a healthy phenomenon, it has gone beyond that.
I was always happy to point out that our (Religious Zionist) camp does not fail in the realm of sinat chinam in this matter. For example, we would donate to all yeshivot and welcome guests of the "opposing camp." I have been very pained recently at the lack of respect toward those in the other camp, for example by removing their protest signs and threatening against protests against chillul Shabbat. Since when ischillul Shabbat sectarian within the religious community?! Where is the respect for the dignity of our fellow human being, especially for those who keeps Torah and mitzvot even if we think they are "too religious"? Haven’t we been affected by their tactics, the ones we have rejected in the past?
Let the time of the Three Weeks serve as a reminder of the sins of the past, which should keep us away from sinat chinam in our times.