Chofetz Chaim – Introduction (2)
If we look closely at our ways and ask which sins are the main cause of our long exile, we will find many. But the sin of the tongue stands above them all, for many reasons.
First, it was the main cause of the exile. So as long as we do not fix this sin, how can the redemption come? If this sin sent us out of our land, all the more so it will stop us from returning to it!
Also, we know that the exile was decreed on us already at the time of the sin of the spies, as it says (Tehillim 106:26-27), "He raised His hand to them to make them fall… among the nations and to scatter them in the lands," as Rashi explains there. The spies' sin was lashon hara. So we must fix this sin before the redemption.
We also find clearly that this sin brings hard slavery on Israel. In parshas Shemos (Shemos 2:14) it says, "Indeed, the matter is known." The Midrash Rabbah says openly (Devarim Rabbah 6:14): "The Holy One said - In this world, because there was evil report among you, I removed My Presence from among you, but in the future to come, etc." And in parshas Vezos Haberacha the verse says clearly (Devarim 33:5): "There will be a king in Yeshurun when the heads of the nation gather; together the tribes of Israel." Rashi explains: when will there be a king in Yeshurun? Only when the tribes of Israel are united and not split into groups - and it is known that the splitting comes from lashon hara.
Besides that, how can we receive the blessings from Hashem that we long for, if we are used to this sin? The Torah has an explicit curse about it (Devarim 27:24), "Cursed be he who strikes his fellow in secret" - which speaks about lashon hara - in addition to the other curses written there. We also know from the Gemara in Arachin (15b) that this sin has no limit, so much so that our sages say whoever does it is like someone who denies a basic belief, Heaven forbid. And the Yerushalmi in Pe'ah (1:1) says that a person is punished for this sin in this world, and the main punishment waits for the World to Come.
Later in the Opening, and in my book Shmiras Halashon, I bring all the sources from the Talmud, the Midrash and the Zohar on this topic. Whoever reads them and thinks about them carefully will feel his hair stand up at how great this sin is.