“The tongue like a sharp knife… Kills without drawing blood.”
It is said that a dull knife is far more dangerous than a sharp one. The idea being that a dull jagged blade will cut with tearing and great mess, whereas a sharp edge will cut with surgical precision and no tearing. Using this metaphor with the tongue, which of course forms our words, sends a powerful message. It is saying that words can be very powerful, and can do great damage, can even kill, but without drawing actual blood.
Words can be used to command an army to kill a large number of people, destroy cities, and execute innocent people. They can also be used to hurt people around us, those we don’t know, and even people we love. If we are mindful of our words, and respect their great power, like a sword, we will know to hesitate before drawing this deadly weapon. When we get angry, we may speak horrible, deadly words without thinking, and without intending the maliciousness that they will be perceived as.
We must keep our words sheathed, ready but knowing that unless we want to do damage, we should wait to speak until we know how to control the words that come out.