Sirach 28:12
Ben Sira, Ecclesiasticus11 A hasty quarrel kindles a fire, and a hasty dispute sheds blood. 12 If you blow on a spark, it will glow; if you spit on it, it will be put out; yet both come out of your mouth. 13 Curse the gossips and the double-tongued, for they destroy the peace of many. 14 Slander has shaken many, and scattered them from nation to nation; it has destroyed strong cities, and overturned the houses of the great.
Leviticus Rabbah 33
Aggadah"And Ad-nai said to Moshe... 'When you sell goods to your people [you shall not wrong one another]' (Leviticus 25:1-14)." Another verse: "Life and death and in the hand of the tongue", the translation of Onkelos 'mystromakerion' [an eating utensil, a side is a spoon the other a knife] death from this side and life from this side. Bar Sira said: 'there is a fiery coal in front of him, if he blows on it it catches fire, if he spits he puts it out.' Rabbi Yannai said: if he had a piece of bread in front of him and ate it without tithing, this is 'death by the hand of the tongue'; if he tithed it before eating, this is 'life by the hand of the tongue.' Said Rabbi Chiya bar Abba: If he had a basket of figs. If he ate them before he separated off tithes, then it is death by the hand of the tongue. If he separated off tithes and then ate, it is life by the hand of the tongue. Rabbi Shimon ben Gamliel said to Tavi his servant, "go purchase for me the best food from the market." He went and bought for him a tongue. He said to him "go purchase for me the worse food from the market." He went out and bought him a tongue. He said to him, "What is this? When I say to you to the best food, you buy me a tongue, and when I say to you the worst food, you [also] buy me tongue!" [Tavi] said to him, this is the best and this is the worst! When it is good, there is none better than it, and when it is bad, there is no worse than it." Rabbi made a feast for his students, and brought before them tender tongues and tough tongues. They began to choose for themselves the tender tongues and left alone the tough tongues. He said to them, "Know what you are doing! Just as you are choosing the tender [tongues] and leaving alone the tough ones, so shall your own tongues be with one another. Thefore Moshe warned Israel, 'and when you sell goods... [you shall not wrong one another]'
Notes and References
"... The book of Ben Sira, a work at the fringes of the Jewish biblical canon, posed a different sort of problem for the rabbis.13 The rabbis affirm that Ben Sira is not included in the biblical canon (t. Yad. 2:13). Nevertheless, it is clear that the book enjoyed widespread popularity in both rabbinic and non-rabbinic circles (Leiman 1991, 99–102). Indeed, the content of Ben Sira is consistent with rabbinic wisdom statements and is cited frequently in rabbinic literature (Segal 1958, 37–42); several rabbis even take credit for teachings found in the book (Pirkei Avot 4:4; b. Shabbat 11a). There is not an obvious pattern to the subject matter or verses that the rabbis cite, although Tal Ilan (2006) notes that a significant percentage of them concern women. Other subject matter quoted include attitudes toward esoteric knowledge, appropriate social conduct and manners, and hospitality (Labendz 2006, 381). Of course, Ben Sira’s famous identification of wisdom with Torah resembles that found in rabbinic literature, even if the rabbis never quote Sirach 24. Whether the rabbis would be willing to rely upon a non-canonical work as a source of wisdom regardless of its content, however, was an open question ..."
Mermelstein, Ari "Wisdom and the Rabbis" in Adams, Samuel L., and Matthew J. Goff (eds.) Wiley Blackwell Companion to Wisdom Literature (pp. 368-388) Wiley-Blackwell, 2020