Shakespeare uses the supernatural in "Macbeth" the way he does in many of his other plays where supernatural events occur. These events add a sense of mystery and suspense to the action. In addition, during the time when Shakespeare wrote these plays, many people believed in supernatural events. The audience was probably extremely familiar with the idea of witches and the idea that they were considered evil. Thus, by listening to the witches, Macbeth shows his ambition and tendency towards evil as he tries to help make the witches prophecies come true. The witches add to the evil intentions of Macbeth and his wife and we see their actions, not only in the light of an ambitious people, but also a couple who can be tempted to evil simply by suggestion.
The attitude toward the supernatural in Shakespeare's tragedy Macbeth is reflective of the views of the supernatural in the Elizabethan era in which the play was written. The supernatural elements in the play set the tone and mood and advance the plot.
During Elizabeth I's reign, it's estimated that more than 200,000 women were accused of witchcraft and punished for this crime. Elizabethans in general did believe in witches. They believed that they had sold their souls to the devil in exchange for certain powers. Witches were thought capable of changing the weather, casting spells, and prophesying future events.
In Macbeth, the witches, known as the Weird Sisters, are the first characters to appear onstage. They enter amidst thunder and lightning, which sets an ominous tone for the play. The witches call to their "spirit friends," which are a cat and a toad, creatures that are associated with black magic. This further cements the ominous presence of the sisters. They say "Fair is foul and foul is fair, let us fly away through the fog and filthy air." These lines foreshadow future events.
The sisters reappear in Act 1 scene 3, and more of their characters is revealed. One sister talks of having control of the four winds. The first witch talks of getting revenge on the husband of a woman who wouldn't share her chestnuts with her. The other sisters support the first witch's mission of revenge. When the sisters encounter Macbeth and Banquo, they prophesy future events for both men. The prophecy drives Macbeth's ambition, and he devises a scheme to accomplish the prophecy that he will be king. This reveals Macbeth's character, and it contrasts his character with that of Banquo. Banquo reasons:
"The agents of evil often tell us part of the truth in order to lead us to our destruction. They earn our trust by telling us the truth about little things, but then they betray us when it will damage us the most."
Banquo fights against the seeds of destruction that are planted in his mind by the Weird Sisters, whereas Macbeth nurtures and develops them.
In Act 2 scene 1, Macbeth sees a floating dagger coming toward him. This is a physical manifestation of the thoughts he is harboring about murdering Duncan. He says the dagger is leading him toward the place he was going already and that he was planning to use a weapon just like the apparition to do the deed that will fulfill the prophecy. This dagger both frightens and impels him.
Another supernatural element is the voice that Macbeth hears in Act 2 scene 2. He says:
"Still it cried, “Sleep no more!” to all the house.“Glamis hath murdered sleep, and therefore CawdorShall sleep no more. Macbeth shall sleep no more.”
The supernatural is very much applauded. It DOES add mystery & suspense, as ms-mcgregor mentioned. The characters take everything said by the witches seriously & allow their words & the supernatural events to aid them in their decision making. The supernatural also effects the mood of the scene.