The first person who influences Macbeth into his sin is not really a person at all. The weird sisters, as is their art, wreak havoc with Macbeth’s mind and life. From the moment they are introduced, their every word affects Macbeth’s actions. They are the characters that put the idea of becoming king in Macbeth’s head to begin with: “All hail, Macbeth! Hail to thee, Thane of Glamis! / All hail, Macbeth! Hail to thee, Thane of Cawdor! / All hail, Macbeth! Hail to thee, that shalt be King hereafter! (1.3.48-50).” By addressing Macbeth first as he is, then with a title that he is but does not yet know of, and finally with a title he must take action to attain, they encourage him to take the actions necessary. Their words are a promise to him that he will succeed if he murders Duncan. Of course, the weird sisters are not responsible only for the first blood that covers Macbeth’s hands. It is the sisters’ prediction that puts Macbeth on the course to kill Macduff: “Macbeth! Macbeth! Macbeth! Beware Macduff! Beware the Thane of Fife. (4.1.71-73),” which finally ends in Macbeth’s death. The weird sisters have a large part in Macbeth’s death as well for they make him “spurn fate, scorn death, and bear his hopes ‘bove wisdom, grace, and fear (3.5.30-33)” by predicting actions but relaying only riddles. For example, the weird sisters predict that “none of woman born shall harm Macbeth (4.1.79-81),” and “Macbeth shall never vanquished be until Great Birnam Wood to high Dunsinane Hill shall come against him. (4.1.92-94).” However, these predictions are only true in part. Macbeth never suspects that Macduff’s caesarean birth could constitute a birth separate from woman, and he never could have imagined that Malcolm’s troops would carry limbs from Birnam Wood to disguise their numbers. Macbeth is tricked by the weird sisters into believing that he is nigh invincible. It is logical to assume, then, that though Macbeth is far from innocent, the sisters share a large part of the responsibility.
The person most responsible for Macbeth’s foolish rise to power is his wife, Lady Macbeth. Lady Macbeth is the sole reason that Macbeth acts on the weird sister’s prophesies. Even before she speaks to him, Lady Macbeth has sworn that her husband will take the King’s place by murdering his lord and kinsman. It is her decision that Macbeth take power, not his own, and her plans that mean the end of Duncan. Lady Macbeth is in control from her first introduction; Macbeth himself is just a tool in her hands. Lady Macbeth feels that she has to take control, for her husband will never take the requisite steps. Macbeth is “too full o’ th’ milk of human kindness to catch the nearest way (1.5.17-19).” Lady Macbeth knows her husband too well to imagine that he will readily accept murdering his King so she makes the plans herself. While this does not excuse Macbeth’s actions—he still killed the King—it may excuse his motives.
When Macbeth is finally subject to Lady Macbeth’s ministrations, her every word is directed at convincing him to go along with her plan: “Hie thee hither. That I may pour my spirits in thine ear, and chastise with the valor of my tongue all that impedes thee from the golden round which fate and metaphysical aid doth seem to have thee crowned withal. (1.5.26-31).” Lady Macbeth curses her husband for his gentle and trustworthy nature, and eventually succeeds in turning him to her cause. In addition, Lady Macbeth is plagued by the same nightmares and death of sleep as Macbeth. Her sleepy soliloquy in Act 5 (5.1.38-43, 45-48) belies her guilt. In many ways, Lady Macbeth is guiltier than Macbeth himself is, for she never wavers in her purpose to see Duncan dead and Macbeth crowned in his place.
Macbeth is never resolute in his wife’s dreadfully designed plan. It takes much convincing before Macbeth even accepts the plan at all. He only accepts it when he does because of the curses that Lady Macbeth piles on him. Macbeth is a man, and like a man, he will do anything to prove how tough he is, especially when someone is questioning his veracity. In Macbeth’s defense, he twice told his wife that they would not carry out the plan, once implicitly, “we will speak further (1.5.72),” and once explicitly, “we will proceed no further in this business (1.7.31).” Macbeth even tries to defend his manhood against his wife’s attacks, “prithee, peace! I dare do all that may become a man; who dares do more is none (1.7.45-47),” but he is never successful for Lady Macbeth is simply too strong in her will. No matter how courageous Macbeth is on the battlefield, Lady Macbeth’s words can unseam him from the nave to the chops at any moment when he is at home.
Macbeth is a victim, of his wife and the weird sisters as well as of his own ambition and weak mindedness. His ambition is his tragic flaw, and his redeeming quality is his true nature. When Macbeth is finally stripped of all pretenses, of his crown and his wife, his predictions and his protections, he is nothing but a warrior, and thusly he faces Macduff the final time, as a warrior. Macbeth reclaims much of his lost honor in his final scene because he reclaims some of his lost self. Macbeth is not free of any responsibility, far from it, actually.
However, the knowledge that others motivated the vile murders that so often are heaped entirely on Macbeth reveals much about his character. Macbeth is not a bad man, he is just naïve.