Speech is a defining characteristic of human beings, part of our self-definition as individuals and members of groups. Judaism sees speech as a fundamental theological and ethical category, warning that “death and life are in the power of the tongue” (Proverbs 18:21).
The biblical book of Genesis portrays the creation of the world as accomplished by speech. Step by step, from formless light to the fully formed human being, God constructs the universe through no more than a series of “Let there be…!” statements. Biblical wisdom literature is aware of both the help and the harm that may be done by language, and the Psalmist advised anyone who desires a good life to “guard your tongue from evil and your lips from speaking deceit” (Psalms 34:14).
The tradition of rabbinic learning is replete with moralistic guidance and, to a lesser degree, explicit legislation about the use of speech. Malicious speech is said to expel God’s presence from the world, and God is portrayed as saying of one who indulges in malevolent talk, “I and he cannot both dwell in the world.” With some bombast but equal earnestness, the Babylonian Talmud suggests that one who speaks maliciously denies basic theological principles, and the Palestinian Talmud ranks such behavior as equivalent to the three cardinal transgressions–idolatry, murder, and forbidden sexual unions–put together.
Slander–the deliberate dissemination of damaging untruths–is banned by Jewish law. So is the malicious dissemination of damaging truths, which is labeled lashon ha-ra (“evil speech”). In fact, every sort of talk about others, true or false, comes under a cloud of suspicion in Jewish moralistic and legal literature. One should not infer from the lack of a clear distinction between the treatment of truth and falsehood here, however, that truth is not valued over deceit, but that spreading even truth can be destructive–and that, on the other hand, Jewish sources recognize that competing values may occasionally need to take precedence over the importance of being truthful.
These include the protection of life and limb and the maintenance of tranquil relations among family members, friends, and acquaintances. However, one must protect oneself against verbal attack, and the Jewish ethical tradition recognizes our legitimate need to confront someone who has done us harm.
Another sort of regulated speech is the taking of vows and oaths. The seriousness with which the Bible treats such self-imposed undertakings leads post-biblical Jewish sources to discourage the use of language in this way. We also encounter in Jewish tradition legal and moralistic discussions about speech intended to deceive and defraud others, robbing them of their emotional well being or valuable time or building up false expectations, even if no financial harm is inflicted. Such speech, too, is banned by Jewish law.
The “Hafetz Hayyim,” Rabbi Yisrael Meir Kagan of Lithuania (1838-1933), is universally recognized as one of his generation’s greatest scholars of Jewish law, despite his having held no formal rabbinic position. He established his reputation on the basis of his first book, in which he developed the laws banning malicious speech, and it is by the title of that landmark work, “Hafetz Hayyim”, that he is known.