There is an ancient fable about a monster known as Proteus who had the power of assuming many shapes and appearances. He could become a tree or a pebble, a lion or a dove, a serpent or a lamb. He seemed to have little difficulty in passing from one form into another.
That fabled creature reminds me of the human tongue. It can bless or curse; it can express praise or whisper slander; it can speak a word or encouragement or spread the poison of vindictive hatred (James 1:10, 11).