Shemirat HaLashon שמירת הלשון

And there is yet another reason for this. It is known that in accordance with a man's ordering of his traits in this world is the corresponding arousal of this trait in the world above. If it is his way to overlook offenses and to deal with men with the traits of lovingkindness and mercy, he thereby arouses, above, the trait of mercy, and the Holy One Blessed be He is merciful to the world because of him. And "from the fruits of a man's mouth, his soul will be sated." And he, too, will merit the mercies of the Holy One Blessed be He, and his offenses will be forgiven, as Chazal have said (Shabbath 151b): "All who are merciful to men are granted the mercies of Heaven," and (Yoma 23a): "All who overlook offenses to themselves have their [own] offenses overlooked [by Heaven.]" As stated in the Zohar, Parshath Emor:

"We learned: 'The deed above is awakened by the deed below. If a man does a deed appropriately below, lovingkindness is awakened above, and it reposes [itself] on that day, and it [the day] is crowned by lovingkindness for his sake. And if a man conducts himself mercifully below, he arouses mercy on that day, and it is crowned with mercy for his sake. And then, that day stands for him to be a defense at the time that he needs it, etc. By the same measure that a man measures with, he is measured by. Happy is he who shows a "kosher" deed below. For on that deed depends everything, to arouse its [heavenly] counterpart thereby.'"

And if it is his trait in dealing with people never to forego anything that is his and never to be merciful to them, he intensifies thereby, above, the attribute of din against the world and also against himself. For by the measure that a man measures with he is measured by, and none of his deeds will be overlooked. And this is the intent of Chazal (Bava Metzia 30b): "Jerusalem was destroyed only because they set their ways on the din of Torah." Now did they not have many sins, as indicated in Scripture? But according to the foregoing, it is clear. If they had overlooked offenses, the Holy One Blessed be He would have pardoned them accordingly. But they had set their ways not to forego anything for their friends beyond the parameter of din, wherefore the Holy One Blessed be He was exacting with them likewise.

And if one speaks lashon hara against his friend and arouses din against him, he arouses thereby, above, "prosecution" against Israel, and he thereby gives Satan power to prosecute Israel, as stated in the holy Zohar, Parshath Pekudei:

"There is a certain spirit that stands over all those ‘men of lashon hara,’ and when men are roused with lashon hara, or when that one man is roused with lashon hara, there is roused up that unclean, evil spirit above called "sachsucha" [contention], and it comes to repose upon that arousal of lashon hara initiated by men, and it thereby causes the awakening of lashon hara, the sword, and slaughter in the world. Woe to those who arouse that power of evil and do not guard their mouths and tongues and are not fearful of this, not knowing that on the lower awakening depends the higher awakening, both for good and for evil, etc. And all [of these] are prosecutors to arouse that great serpent to prosecute the world. And all because of that lower arousal of lashon hara.”

And when we reflect but a little upon this awesome thing, we understand immediately why the Holy One Blessed be He is more severe with this sin than with all others, to the point that He refuses to associate with the man of lashon hara at all to rescue him from his troubles, as will be adduced, please G-d, below in the name of the Sifrei, and as is written in the Zohar, Parshath Shelach: "R. Shimon said: 'The Holy One Blessed be He pardoned all, except lashon hara.'" For it is known that the love of the Holy One Blessed be He for His people, Israel, is exceedingly great, as Scripture states (Jeremiah 31:19): "Is not Ephraim a dear son to me, or a child that I dandle, etc.?" When a man has a dear son or a child that he dandles, and he sees that he is not acting properly, still, he "covers up" for him in his great love for him. And even though he chastises him at times, it will be with compassion and pity. But if some men come to him once or twice and tell him about his sons' waywardness, how he argues and wrangles with people for nothing, how he shames and insults everyone, then certainly he will grow angry with him and beat him and shame him for this. And who caused all this? The teller. The same is true in our case. The Holy One Blessed be He, in His great love for Israel, even though He knows all that is done in secret and in the open (as it is written [Jeremiah 23:24]: "Will a man hide himself, etc.?"), still He will not arouse Himself against them to do them evil, as it is written (Numbers 23:21): "He has seen no iniquity in Jacob" [see Rashi there]. But, if the accuser comes to Him and tells Him of this, He must give him some kind of answer [just as "the kingdom of the earth" must respond when someone cries out before them over some injustice done to him.] For thus has the King of the world established it, that a man's affairs are mediated through defenders and prosecutors.

Now it is known, that the upper "arousal" is dependent on the lower. Therefore, if the trait of peace is found in Israel, and there are no slanderers among them below, then in the upper world, too, Satan cannot prosecute them — even for the severest sin of all, idol worship, G-d forbid, as stated in Midrash Shir Hashirim, that even (G-d forbid) if Israel is idolatrous, but there is peace among them, the Holy One Blessed be He says, as it were: "Satan will not touch them," as it is written (Hoshea 4:17): "Ephraim is bound to idols — let him be!" The intent here is that the Holy One Blessed be He has implanted it in Satan that in such an instance [i.e., when Israel are at peace among themselves], Satan cannot touch them at all. And thus have Chazal said (Yerushalmi Peah 5:1), that the generation of Achav, even though they were idolators, would go down to war and win, because there was no slander among them. The proof — they did not slander [(to Achav)] Ovadiah, who sustained the one hundred prophets [who were hiding from Achav]. And, as I have written below, (Chapter IV), "measure for measure" is a [guiding] principle in all affairs. Therefore, if one suppresses himself and muzzles his mouth against speaking demeaningly against his friend and arousing strife against him, so, above, the Prosecutor, above, will not be able to open his mouth to speak accusingly. As opposed to a situation where there is slander in Israel below. For aside from the slanderer's arousing prosecution against himself because of his sins (as we shall explain below in the name of Chazal), he arouses the power of prosecution against Israel in general. For through this, Satan comes and prosecutes Israel for their sins, and calls for din against them; and [the L-rd], as it were, is "compelled" to punish them for this. And who caused all this? The speaker of lashon hara below.

[And, in my view, this is the intent of the verse (Bamidbar 23:21): "He does not see iniquity in Jacob … the L-rd his G-d is with him": When does He not see iniquity in Jacob? When the L-rd his G-d is with him. But when there is, G-d forbid, lashon hara in Israel, which leads to departure of the Shechinah, as stated in Midrash Rabbah, Parshath Shoftim, then, G-d forbid, He does probe their deeds.]

And from all this we can understand the greatness of the hatred that the Holy One Blessed be He bears to the "teller." For though the father strikes his son, being compelled to do the teller's will, understanding the thing to be true — in any event, great hatred is aroused in his heart against the teller, recognizing that his motive is not to benefit his son, but to censure him. How much more so is this true in our case. For it is known that the Holy One Blessed be He loves a man more than he loves himself, and He desires only the good of Israel, and that they not be slandered at all. As Chazal have said on Isaiah 6:6: "And in his [the angel's] hand, a coal [ritzpah]," the Holy One Blessed be He saying to the angel: "Let the mouth be crushed [("retzotz peh," like "ritzpah")] that slandered My sons." And the speaker of lashon hara causes the opposite of all this [(love between G-d and His children)], for which reason he is detested in the eyes of the L-rd.

Now if the man of heart reflects upon the aforementioned holy Zohar, and sees with a "knowing eye" what is destined to result from his speech, he will be filled with fear and trepidation [at the thought of] speaking lashon hara against his friend. For if a man were told to enter the sanctuary of the L-rd by himself or to send a messenger in his place to stand before the ark of His covenant and prosecute all of Israel and not speak falsehood of them but only what he knows to be the truth, is it not obvious that even the worst man of Israel would not take upon his soul a sin as horrendous as this? And is this not exactly the case with lashon hara?, the slander that he utters with his mouth arising before the Blessed One's throne, as stated explicitly in Tanna d'bei Eliyahu, Chapter 18: "Just as the wicked speak lashon hara, which ascends before the Throne of Honor, etc." And by this he arouses the Great Prosecutor against the children of Israel, as per the aforementioned holy Zohar.

From all of this, we can understand the greatness of the punishment exacted for this sin in this world and the next. And, therefore, King David, may peace be upon him, exhorted us that if it is our desire to live eternally in the world to come and to enjoy good days in this world, the beginning of all is to guard our tongue from evil. And how much should we be ashamed and abashed before the Holy One Blessed be He to whom we pray on the Days of Awe: "Silence the prosecutor and let the defender take his place," when we ourselves, through our lashon hara, arouse him [the prosecutor] and give him the power to prosecute! May the L-rd repose among us love and brotherhood, peace and friendship!