Rebuilding through Teshuva
The Gemara says: In every generation that the Beit Hamikdash is not rebuilt, it is as if in that in that generation it was destroyed (Yerushalmi, Yoma 1:1). The reason for this is that if we would do sincere teshuva (repentance) for the sins that caused the Beit Hamikdash to be destroyed, then we would merit seeing it rebuilt. The fact that it is not rebuilt yet is a sign that we are continuing in the wrong ways that led to its destruction. In fact, the Rambam says that the entire purpose of a fast day is to contemplate and repent for our sins, and our ancestors’ sins, that were, and continue to be, the cause of tragedies (Mishneh Torah, Hilchot Ta’anit 5:1). Based on this, it is incumbent on us to understand, and thus fix, the actions that caused the Beit Hamikdash to be destroyed, and which are currently preventing it from being rebuilt.
The Gemara says that the First Beit Hamikdash was destroyed because of the three cardinal sins: idolatry, illicit relations, and murder. The Second Beit Hamikdash, though, was destroyed on account of baseless hatred (Yoma 9b). Since the First Beit Hamikdash was destroyed because of idolatry, illicit relations, and murder, and the Second was destroyed because of baseless hatred, the Gemara concludes that baseless hatred is akin to the three cardinal sins. The Gemara, in a different location, also equates the sin of lashon hara with these three cardinal sins. Based on this and other proofs the Chafetz Chaim says that, indeed, during the Second Beit Hamikdash baseless hatred manifested itself in lashon hara, and it was because of lashon hara that the Beit Hamikdash was destroyed (Arachin 15b).
This concept though is hard to grasp because we know that when it comes to practical halacha we do not treat the sin of lashon hara as harshly as the three cardinal sins. For example, a person is commanded to give up his life rather than commit idolatry, illicit relations, or murder (Sanhedrin 74a). This command, though, does not apply to lashon hara. How can the Gemara equate the severity of lashon hara with these grave sins?
Rabbeinu Yonah in his classic work Shaarei Teshuva suggests several answers. In contrast to the three cardinal sins, the sin of speaking lashon hara is always available. There are more opportunities to speak lashon hara than, for example, to commit murder. Therefore, even though the sin of lashon hara itself is not as severe as the three cardinal sins, it adds up to reach their severity, as it is done many more times.
Furthermore, unlike the three cardinal sins, which are viewed by even those who commit them as crude acts, lashon hara is not looked at as being truly bad, since after all, it's only speech. In fact, many people feel no remorse at all after speaking lashon hara. Because of this, unlike the three cardinal sins, people don’t feel the need to do teshuva for the sin of lashon hara.
To go even further, even for those who do try to do proper teshuva it is very hard. First of all, since it is available so many times a day it is a very difficult habit to break. Furthermore, since one part of the teshuva process is to ask forgiveness from everyone whom one spoke lashon hara about, attaining full repentance becomes very difficult to accomplish (for the practical application of this halacha, see Halichot Shlomo, Aseret Yemei Teshuva, p. 45, comment 24). Finally, since one component of teshuva is charata, regret,even those who do repent do not have complete teshuva because they don’t fully appreciate the severity of the sin they committed to have the proper amount of charata. Rabbeinu Yonah explains that the combination of all these factors make lashon hara as severe as the three cardinal sins(Sha’arei Teshuva 3:201-210).
If lashon hara had the power to destroy the Beit Hamikdash, then it certainly has the power to keep it from being rebuilt (Shemirat Halashon, chelek II perek 7). So what is the solution? Abstaining from speech altogether is impractical and at times impossible. Even if it were possible it wouldn’t help regarding the sin of accepting lashon hara, and also wouldn’t help in situations when halachically one is obliged to share information. The only real way to deal with this critical issue is to learn the halachot constantly, so one may know exactly what is and what isn't allowed. This is the only way we can sensitize ourselves to an area in halacha that is often overlooked and ignored.
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