Final answer:
Shakespeare repeatedly emphasizes King Duncan's goodness to contrast with Macbeth's treacherous ambition, highlight the moral descent, and elicit audience sympathy for the murdered king.
Step-by-step explanation:
Shakespeare emphasizes King Duncan's goodness throughout the play Macbeth to heighten the gravity of Macbeth's betrayal and the resulting regicide. By repeatedly showcasing Duncan's noble qualities and his gracious interactions with other characters, Shakespeare creates a stark contrast to Macbeth's ambition and treachery. Highlighting Duncan's goodness not only underscores Macbeth's moral descent but also serves to elicit sympathy from the audience for the unjustly murdered king.
Duncan's dialogue is full of references to honor, generosity, and kindness. Phrases like "They smack of honour both," "our honour'd hostess," and calling Macbeth "noble" emphasize his ability to recognize and reward the good qualities in others. This repeated affirmation of Duncan's virtue makes the plot to murder him all the more heinous and tragic.
Furthermore, Lady Macbeth's manipulation and plans to murder Duncan are made more by her acknowledgment of his goodness. She understands that Duncan is a guest who trusts them, which she plans to exploit, thus heightening the treachery.