Taken in its literal sense, every word does something, though of course if it is the intended effect of the speaker is a completely different point. This statement does identify the power of speech and that it always has some kind of effect. In a sense, every utterance or act of speech is a "thing" - speech itself is a very powerful tool that has been used throughout the ages to persuade, defend, justify and attack, to give just a few uses. However, I am guessing that your question actually comes within a more specific context that relates to some particular field or a more directed topic. Is it the art of rhetoric that your question is trying to focus on, for example, or is it a different area? You might want to rephrase your question making it more specific and directed towards a particular area or point so we can help you answer it.