Although Macbeth ultimately murdered King Duncan, his decision to kill was influenced by many. Macbeth’s immediate thoughtless action was influenced firstly by the three Witches and then by Lady Macbeth who had put him under pressure not to miss the golden opportunity for fulfilling his deep ambition to be king.
The Witches play an important role in the killing of Duncan as they are the ones who had planted the idea into Macbeth’s mind. The Witches appear amongst thunder and lightning. This dark weather creates an atmosphere of mystery and evil which will soon take place in Scotland. The Witches possesses supernatural powers to cause damage and disrupt the natural order of nature (“Fair is foul, and foul is fair”), but they are not powerful enough to achieve their evil schemes on their own. This is evident when the witches’ plan to cause a sailor disaster after his wife refuses to give the witch chestnuts. “Weary sev’n-nights, nine times nine shall he dwindle, peak and pine: Though his bark cannot be lost, Yet it shall be tempest-tossed.” The Witches speak the plans for causing chaos by giving wind and causing storms, but at last they mention that they cannot loose or destroy the ship, but they can cause some confusion.
In Shakespeare’s time, the belief in a greater power controlling life was very strong. As long as this diving order was maintained, chaos could not take control. The king was revered as equal to god. And a murder against the king would not only be a crime against the state but more importantly a crime against god. The Witches are believed not to be able to touch the King with their supernatural powers as he is too holy due to the diving right of the kings. This is the reason why Macbeth is essential in planning the murder of king Duncan.
Lady Macbeth too plays an important role in the murder. She is the character who eventually persuades Macbeth to kill the King. Soon after Macbeth’s first meeting with the witches, he writes to his wife Lady Macbeth, describing the prophecies and how he feels about them. “My dearest partner of greatness, that thou mightst not lose the dues of rejoicing by being ignorant of what greatness is promised thee.” In the letter we see the deep relationship between Lady Macbeth as Macbeth calls her ‘my dearest partner of greatness’ as he is writing to inform and ask for her advice in the prophecy. Unknowingly, Macbeth has also planted in the heart of Lady Macbeth the hunger for greater power.
Lady Macbeth declares that Macbeth is “too full o’ the milk of human kindness to catch the nearest way” to kingship. She prays to evil spirit to strengthen her so that she herself could commit the murder. “Come, you spirits that tend on mortal thoughts, unsex me here”. Instead of encouraging Macbeth to wait on the prophecy and do the rightful thing, she is encouraging murder. Lady Macbeth mocks Macbeth by calling his a ‘coward’ which places upon Macbeth high expectation and pressure which leads Macbeth to prove himself before her that he is manly enough to do anything.
All these influence in Macbeth’s life has driven him to continue with the murder. But who plotted the murder? If Lady Macbeth was not told about the witch’s prophecy, she would never have attempted to encourage such a thing. Although Macbeth had a deep desire to be King, he had not taken any action towards his ambition. But the witches did prophecy that Macbeth shall be king, hoping that he would take action. Therefore, I believe that the Witches are responsible in planning for the murder of the king long before they meet Macbeth. Since they themselves could not successfully accomplish it themselves, they have used Macbeth to do what they have plotted while falsely promising Macbeth happiness in accomplishing his ambition.