It is written in the Gemara in Arachin (16a): Rabbi Shmuel ben Nachmani—in the name of Rabbi Yehuda—said that Hashem afflicts a person with tzara’as to atone for one of seven sins and that lashon hara is one of them. The Gemara asks about a contradiction to this. Rabbi Anani bar Sasson said that the me’il (one of the priestly garments) is what atones for lashon hara! The Gemara answers that in actuality both tzara’as and the me’il atone for lashon hara but each one atones for a different type. Tzara’as atones when the lashon hara caused damage, for example, it caused two people to fight or it caused one person to think less of another person. When nothing came out of the lashon hara, then the me’il atones.

From this Gemara, we see that even though lashon hara is a very severe sin, there is atonement for a person who transgresses it.

The Zera Shimshon asks that this Gemara seems to contradict a previous Gemara. Just one amud before (15B), it is written that Rabbi Acha, the son of Rabbi Chanina, said that if a person spoke lashon hara he has no remedy, since Dovid HaMelech declared through ruach hakodesh that anyone who speaks lashon hara is cut-off (kares) from the Jewish nation, like it is written, “yachris Hashem kol sifsei chalakos lashon medabberess gedolos—Hashem should cut off all the ‘smooth-talking’ lips, the tongue which speaks boastfully!”

How can we reconcile these two statements? He answers by asking and answering another question. The Gemara in Moed Katan learns from the pasuk, “tamay tamay yikra, one who contracted tzara’as should call out: ‘tamay tamay,’” that one who contracted tzara’as shouldn’t keep it a secret, but he should publicize it in order that people will pray for his recovery. The Zera Shimshon asks: Why specifically concerning tzara’as does the Torah teach us that one needs public prayer to be saved from a difficult situation, and not in some other difficult situation?

He says that the answer to this question lies in the exact wording of Rabbi Ananni bar Sasson, “if a person spoke lashon hara, he has no remedy, ‘ain lo takonah.’ It is not written, “there is no remedy—ain takonah,” but it is written, “he has no remedy.” He cannot heal himself since he is only one person; however, the whole community has the capability to heal him with their prayers. Therefore, a person who contracted tzara’as should publicize his condition, so that the whole tzibbur together can annul the decree and will be healed.

In other words, when a person is stricken with tzara’as it is as if a heavenly verdict was given. A single person isn’t strong enough to annul a sealed verdict, only tefillas harabim (public prayer).

Tefillas harabim is not the only way to reverse a seemingly final heavenly verdict. Chazal teaches us that exile also has this power. The Gemara (Brachos 56A) says that a curse of a talmid chacham is effective, even if it was said for no reason! For instance, if a talmid chacham curses someone if he won’t do something and, in the end, he did do that thing, the curse is still effective. In other words, a curse of a talmid chacham is like a sealed, final and irreversible verdict. However, the Gemara concludes there that if the person goes into exile that curse is annulled!

According to this—Zera Shimshon explains—we can now understand how it can be that tzara’as atones for lashon hara, even though it is also written that there is no remedy for one who speaks lashon hara. A person who was stricken with tzara’as has to move out of the city where he lived until the tzara’as heals and only then, can he return to his home and to his city. This means that goes into a temporary exile. Exile—as we learnt—has the power to annul even a sealed verdict!

Therefore, even though Dovid HaMelech declared through ruach hakodesh that anyone who speaks lashon hara is cut-off (kares) from the Jewish nation, this is only if he doesn’t go into exile. However, after he leaves his house and city for the whole purification process, he can be spared from the severe punishment.

(The Zera Shimshon only explains how tzara’as atones for lashon hara. However, he doesn’t explain how the me’il atones for lashon hara in a situation that the lashon hara wasn’t effective. I was thinking that—according to what he wrote—it can be explained that since the me’il is bought from the money of all of Klal Yisroel and not from only one individual, it is as if it is owned by everyone and, therefore, it has the power to atone like public prayer!)