James 3:8

The expected triumph collapses. But the tongue no one can tame; it is a restless evil, full of deadly poison. The creature we cannot subdue is not in the wild but in ourselves. What human skill conquers everywhere else, it cannot conquer here.

The tongue is called restless, never fully at peace, and poisonous, capable of dealing death like a serpent's bite. James states the impossibility plainly: by mere human effort the tongue cannot be mastered. This is not despair but honesty, and it points beyond ourselves. What we cannot tame alone, God can transform from within. The heart changed by Christ becomes the only true source of governed speech, for the mouth speaks at last from what fills the heart.