ימח שמו
One gets a sense of a particular culture's deepest anxieties by examining its curses. Curses are an expression of a culture's most undesirable or objectionable state of being. It's like saying, "here's the thing I would dislike the most, and it's exactly what I wish upon you." The inverse of empathy.
The most powerful and damning curse in the Hebrew language translates to "may his name be erased." It is not even addressed to the condemned, but spoken about him in the third person, as if to avoid the denigration of direct interaction. It expresses the greatest punishment imaginable as far as the Jewish tradition is concerned: that one's deeds, one's entire existence should be considered as if it ought never to have been, or indeed never was. It's worse than cursing one's mother. It's worse than excommunication. It is the distillation of thousands of years of existential dread, the terrifying prospect that one's life shall be considered to have been completely devoid of meaning and purpose. It is the curse of being forgotten by history. It is a curse reserved for the most detestable enemy of all things right and just in the world.
In a tradition that believes that God spoke the world into existence, it follows that words carry deep significance, and that speech has an impact on reality, on the lived experience of both the speaker and the audience. It's not too far of a stretch to derive from the significance of the spoken and written word the idea that there could be such a thing as violent speech. To cast a curse that someone ought never to have existed, from such a view, can be thought of as a negation of being in fact; an expression of the desire to kill.