Why might the audience feel disgusted by Macbeth's behavior throughout Shakespeare's play Macbeth?
Although Macbeth is an intelligent man who seems to have upheld the morals of society up to this point in his life, the advent of the three witches’ prophecy that Macbeth will be king sets him on a morally downward spiral. Macbeth's gut reaction upon hearing the prophecy that he will be promoted to Thane of Cawdor and then become king is to justify to himself that this is not a bad thing. As soon as Macbeth greets King Duncan in Act I, Scene 4, he fawns over the king, speaking of “The service and the loyalty I owe / ...by doing every thing / Safe toward your love and honor.” In his heart, however, Macbeth vows to keep his “black desires” hidden. This takes “two-faced” to a whole new level.
To his credit, once the king is at Macbeth’s castle in Act I, Scene 7, Macbeth decides not to harm him. After all, Macbeth reasons, the king is his cousin and trusts Macbeth as one of his thanes and military leaders. Macbeth feels Duncan has been a truly good king and, if he were murdered, all of Scotland and Heaven’s angels would mourn. The minute Lady Macbeth calls Macbeth “a coward in thine own esteem” for refusing to shed blood to become king, Macbeth caves and lets her manipulate him into committing bloody treason.
Although Macbeth's conscience haunts him, he stabs King Duncan in his sleep and lets his wife cover up the murder. After this, Macbeth’s conscience seems to fade quickly. Enjoying the power of kingship, his main concern is his competition—Banquo and his son Fleance—since the witches prophesy that the sons of Banquo are to be kings, not Macbeth’s. In Act III, Scene 1, now-King Macbeth questions Banquo about his afternoon riding plans with Fleance, even telling his friend, “I wish you well on your journey.” Macbeth then sends three hired assassins to murder them. That night at the banquet, knowing full well he’s had Banquo murdered, Macbeth says to his guests, “I drink to the joy of .../ our dear friend Banquo.../ I wish he was here.” What a duplicitous hypocrite! It is disgusting that murder has become Macbeth’s go-to option for any obstacle to his power.
Perhaps as expected, Macbeth and Lady Macbeth become rather distant from each other. When his chief servant Seyton reports to Macbeth in Act V, Scene 5 that Lady Macbeth is dead, Macbeth's appalling response is that his wife should have died at a more convenient time. Although Macbeth initially has some redeeming qualities, he systematically rejects each one. When Macduff produces Macbeth's severed head, the audience hardly mourns at all.
Someone might feel disgusted by Macbeth's behavior for many reasons. First, Macbeth murders Duncan—his king, friend, and kinsman—in a vicious and brutal way. In fact, the manner of the murder is so gruesome that Macbeth is actually haunted by "A dagger of the mind, a false creation / Proceeding from the heat-oppressed brain," even before he commits the deed (Act II, Scene 1, lines 50-51). The scene of the murder was so awful and foul that Macbeth couldn't even bring himself to go back into the room after it was done, saying, "I'll go no more" (Act II, Scene 2, line 65). Thus, not only is Macbeth a murderer, but he cannot even look at what he's done.
As if this behavior weren't bad enough, Macbeth next decides to murder Banquo, the man who seems to be his best friend, as well as Banquo's son. Anxious to retain his throne and upset the Weird Sisters said Banquo would father kings, Macbeth summons three murderers, telling the first two, "Both of you / Know Banquo was your enemy" (Act III, Scene 1, lines 129-130). To convince these men to murder Banquo, Macbeth depicts Banquo as some kind of national villain.
Worst of all is when Macbeth murders Macduff's servants, wife, and children. They are killed, in cold blood, for no reason other than that Macbeth is angry Macduff has escaped him. With Duncan's murder, Macbeth stood to gain the throne. With Banquo's murder (and his attempted murder of Fleance), Macbeth stands to secure his throne. Macbeth gains nothing from murdering Macbeth's servants and family. He commits these murders only to be cruel and exercise his power, saying, "No boasting like a fool; This deed I'll do before this purpose cool" (Act IV, Scene 1, lines 174-175). The murder of innocents, especially the murder of Macduff's wife—a woman who already feels abandoned by her husband—and her young children, would likely disgust an audience.