Chazal said (Arachin 15b) that it is written, "Death and life are in the hand of the tongue" (and its fruit is sweet).
Rabbi Elimelech Biderman, shlit"a:
This was the case of a Jew who, at birth, was not endowed with an intellect and knowledge from Heaven like all his brethren among the children of Israel, but a little less than that in both quantity and quality. When he reached the chapter "The Man of the Temple," they were forced to match him with a girl who was also not blessed with great intellect and broad knowledge. Their lives flowed smoothly, and peace and tranquility prevailed in their home. By the grace of Heaven, the couple had two children (with complete knowledge), and they were educated in Talmud Torah and excelled in their studies.
One day, the "gatekeeper," the Jew's father-in-law, had to send his dear son-in-law a certain package. However, the journey to the groom's distant place of residence was difficult for the father-in-law. What did he do? He went down to the bus station and looked for someone who was going to his son-in-law's neighborhood. When he found a Jew traveling there, they asked, "Do you know a certain yeshiva student from your neighborhood?" The Jew thought for a moment, and inquired: "Who, that crazy boy...?" (-Crazy so-and-so). When the father-in-law realized that he was indeed referring to his son-in-law, he confirmed that this was the man to whom the package was to go, and the Jew agreed to be the messenger and deliver the package to the groom. As he walked back home, the father-in-law began to think in his heart, "And this is my name and this is my memory - the father-in-law of the madman?...'" When he got home, he told his wife about it, and they both agreed: It is a disgrace to us that we have such a son-in-law, we will make sure to save our precious daughter from being bound by a crazy boy! (Apparently, the minds of these couples were not so broad...).
The mother was talking to her daughter about her husband, and within a short time, the fire of the quarrel broke out in the house of the groom and daughter ... Only a few days pass, and the couple began to talk about divorce, may God have mercy on them. The words reached the ears of the Holy Rabbi, the Beit Yisrael of blessed memory, and he immediately summoned Rabbi Baruch Kaminer zt"l, who was one of his close associates and served in many positions related to public leadership. The Rebbe asked Rabbi Baruch to do everything in his power to bring peace to the couple's home, to save their married life, and their children from brokenness and "orphans." When he left the holy place, Rabbi Baruch hurried to deal with the matter. He tried and tried in every possible way to connect the two hawks, but he did not succeed.
It was not long before the husband gave his wife a divorce. And what happened to the sons? - They both went out into an evil culture, Rachel. And now let us look at the terrible thing that happened here – a Jew stood at the bus stop, and at the end of it he asked, "Who, that crazy boy?" and this caused the destruction of the Temple. The man and the woman were thrown into grief and a worldly sigh for being forced to divorce each other, and two "holy souls," the sons of the "crazy man," descended into the valleys of Shaul...And to this day, this man did not know what he caused with a single word that he uttered from his mouth!!
Let us carefully memorize the words of the holy Gemara (Arachin 15b): Rabbi Chama the son of Rabbi Chanina said: Why is it written: "Death and life are in the hand of the tongue" – and is there a hand for the tongue (to kill others like the hand)? To say to you: What hand kills, not even a tongue kills! Could it be that a hand kills only near it, and no tongue kills except near it? The Talmud says: "An arrow" slaughters their tongue (just as an arrow can kill from afar, so too an arrow can kill from afar). It is possible, why does an arrow not kill except up to forty and fifty cubits, and even a tongue does not kill except up to forty and fifty cubits? The Talmud says: "They drank in heaven with their mouths, and their tongues walked in the earth." In other words, in his language, a person can kill from his place to the end of the world, as far as the earth is to the heavens.
