As Macbeth ponders whether suicide, at this point, would be his better option, the avenging Macduff enters the scene with the bold challenge: "Turn, hell-hound, turn." Macduff's choice of the epithet "Hell-hound," recalling his earlier description of Macbeth as a "Hell-kite" (Act IV, Scene 3), confirms the true nature of the tyrant king. But in an equally bold rhetorical flourish, Macbeth warns Macduff that he is invulnerable, as "intrenchant" (uncuttable) as the air itself. Here, he mistakenly imagines that the words of the apparitions are a protective charm, which can keep him from physical injury.
Macduff takes an opposite view. Words alone, whether those of a ghostly prophecy or those of Macbeth himself, are nothing compared to his own wordless anger: The true voice of revenge lies in action, not language. Furthermore, Macbeth should consider the circumstances of Macduff's birth. Macduff now reveals to Macbeth that he entered the world by being "untimely ripp'd" from his mother's womb: He was not, therefore, in the strict sense, "born" of woman. With the short but powerful sentence "Despair thy charm," Macbeth must know that his struggle for survival is over. The penultimate prophecy has come true.
