Hecate knows that Macbeth will not question information given to him but will act upon it. Macbeth is given information that he feels will give him immortality. He is ready to believe only what he feels will benefit him, but he is unable to distinguish the “good” from the “bad”. The “Fair is foul and the foul is fair” statement made by the Witches and by Macbeth in this drama has been reinforced in this Act.
Macbeth is no longer capable of making rational judgments or distinguishing good from evil. Obsessed with this knowledge, Macbeth feels he must take quick action to preserve his future. Macbeth feels he must seek Macduff and kill him and his family to ensure that the blood line is stopped.
Macbeth is out of control and reacts without thought to his actions. He feels he must spill blood to remain in control and powerful. Once again Macbeth has innocent blood on his hands, and again, he feels no remorse. He is driven by his lust to control the situation and flex his power. The fact that Shakespeare allows the act of the murder to be witnessed as it occurs, rather than have it reported, gives the audience a first-hand impression of the evil nature of Macbeth. The senseless murder of Lady Macduff and her son contribute to Macbeth’s demise and reinforces the flaws in his character.
Malcolm confesses to Macduff that his own character is far worse than Macbeth. He says he has committed crimes worse than Macbeth. Macduff states that he feels Malcolm has the birthright to be the king of Scotland and he knows that he is worthy. Malcolm says that he was only testing Macduff’s sincerity. Shakespeare uses this ploy to show that Malcolm is a good man and should be the king. The audience supports Malcolm’s efforts to restore Scotland.
The murder of Macduff’s family is unnecessary and the act of a tyrant. When Macduff learns that his family has been murdered, he is even more determined to seek revenge on Macbeth. Macbeth is seen as a barbaric killer and Malcolm’s cause is reinforced by Macbeth’s actions. The murder is the last event that Malcolm and Macduff can allow; they vow to overthrow Macbeth and reclaim Scotland for the people.