After Duncan names his son, Malcolm, Prince of Cumberland and heir to the throne, Macbeth is overcome with jealously and once again fantasizes about being king. The Prince of Cumberland to Macbeth is now "a step which I must fall down, or else o’erleap,/ For in my way it lies. Stars, hide your fires,/ Let not light see my black and deep desires;/ The eye wink at the hand; yet let that be/ Which the eye fears, when it is done, to see" (1.4.48-53). This is the point where Macbeth commits his first sin. He is now committing in his heart the act of killing Duncan. He is asking for the sky to hide what he is planning to do and for his mind to not object or even look at what his hand will be doing. Macbeth has given into temptation, and at this point, has done the deed of murder in his heart.
Macbeth, the ever changing character, changes his mind for a brief moment a few scenes later. He muses over the pros and cons of murdering Ducnan. Guilt overwhelms Macbeth for two reasons. Macbeth is "his kinsman and his subject," and "his host,/ Who should against his murder shut the door, not bear the knife myself" (1.7.13-16). Macbeth should be protecting his guest, not killing him. Macbeth has no basis for committing the deed but only for "vaulting ambition, which o’erleaps itself/ And falls on th’ other" (1.7.27-28). Macbeth realizes that his own ambition, one of his weaknesses, is the only thing that would give him reason to kill Duncan. He can find no other reason, so Macbeth decides he "will proceed no further in this business" (1.7.31). Macbeth has made up his mind, but it does not take much prodding from his wife, another weakness of Macbeth, to change his mind again. Macbeth easily gives in to his wife’s ambitious plans, and is "settled, and bend up/ Each corporal agent to this terrible feat" (1.7.79-80). Macbeth has made up his mind to kill Duncan.
Macbeth will also put on a front to cover up his real feeling, for "False face must hide what the false heart doth know" (1.7.82). It is therefore hard, from now on, to tell what Macbeth is really thinking when talking to others in the play. That is why his asides and soliloquies are so important. Right before he is to go and kill Duncan, Macbeth is alone talking to himself. He starts to fantasize and dream about killing Duncan and sees an imaginary dagger before him (2.1.30-63). This shows how he is beginning to lose his mind and common sense. This will grow as the play progresses. Right after he kills Duncan, Macbeth again tells his wife of these strange images and voices he heard while in Duncan’s chamber killing him (2.2.20-40). He is starting to lose his mind even more, although he shows a little remorse by not wanting to go back into Duncan’s chamber when his wife wanted him to, because he is "afraid to think what I have done;/ Look on’t again I dare not" (2.2.48-49). This shows Macbeth has not completely tossed aside his conscience yet. He shows here that he is feeling regretful about what he just did.
Macbeth is now the new king, but "to be thus is nothing,/ But to be safely thus. Our fears in Banquo/ Stick deep, and in his royalty of nature/ Reigns that which would be fear’d" (3.1.47-50). Macbeth has gotten over the fact that he killed Duncan and is ready to strike again. He gives less thought to killing Banquo who is now a potential threat to him. He does not go back and forth as he did in whether he should kill Duncan or not. This shows how he has declined morally. He is getting closer to the point of totally throwing off the reigns of his conscience. His ambition to be king at all costs propels him to murder one of his best friends, Banquo. After he kills Banquo, he hardly shows any remorse like he did with Duncan. He is progressing down the road to becoming totally evil.
Later on at the feast, Macbeth tries to make his "face vizards to our hearts, disguising what they are", but ends up revealing his madness instead (3.2.33-34). He is terrified by the sight of Banquo’s ghost at the feast. This shows more of the deterioration of Macbeth’s mind. He is acting just like he did before he killed Duncan and afterwards only this time it is worse. He has gone totally nuts this time (3.3.92-106).
Macbeth now realizes that he is "in blood/ Stepp’d in so far that, should I wade no more,/ returning were as tedious as go o’er" (3.4.135-137). At this point, Macbeth has decided to do whatever it takes to stay king. It would be easier to press on than to turn back. He has shed so much innocent blood, "yet but young in deed" (3.4.145). Macbeth has a long way to go.
At this time in the play, Macbeth stoops to actually wanting to see the witches, for he is "bent to know/ By the worst means" what lays in his future (3.3.133-134). Macbeth is now seeking out the witches rather than them seeking him. This shows the selfishness and evil in Macbeth. He gets very bold with them and tells them that if they "deny me this,/ And an eternal curse fall on you" (4.1.104-105). Macbeth is actually threatening to give a curse to the witches. He is getting more evil.
Macbeth makes another major turning point in his character a little later, for from now on, "the very firstlings of my heart shall be/ The firstlings of my hand. And even now,/ To crown my thoughts with acts, be it thought and done" (4.1.146-149). Macbeth is no longer going to give any thought to ideas that pop into his head; he will just do it. He will do thing on an impulse. His first act with this mindset is to kill off Mcduff’s entire household (4.3.75-80). He is declining morally so much, that he does not even think about consequences anymore, but just does it. He has gotten to the point where he does not care anymore. Macbeth is losing all common sense. He is turning totally evil.
Macbeth still shows concern for his wife’s ill condition, however, but this does not last for long either (5.3.40-44). When she dies, his only response is that "she should have died hereafter" (5.4.17). He shows no sorrow or emotion over the death of a wife he had loved. This shows how much his mind has deteriorated and how evil and corrupt he has gotten. Macbeth has now completely lost it. He is now totally evil. He has lost the meaning and sanctity of life for he says that "Life’s but a walking shadow, a poor player, / that struts and frets his hour upon the stage, / and then is heard no more. It is a tale/ Told by an idiot, full of sound and fury, / Signifying nothing (5.5.24.28). Life has no meaning to him anymore. It is fitting that when Macbeth finally gets to this point, that he dies soon after. Macbeth loses his meaningless life.
Macbeth took a steady trip down the road to self destruction. He started as a loyal, brave soldier. When given the praise and esteem of men, his ambition started tempting him to want more. Through much struggling in the mind, inner turmoil, and with the prodding of his wife, he gave in to his ambition and killed Duncan. After this, Macbeth slowly loses his conscience, common sense, and purposefulness, and gets more and more evil, impulsive, and insane. It gets easier and easier for Macbeth to murder. He finally gets to the point where he does not even care about his wife’s life or his own. Macbeth made a complete journey from a person who was basically good to a person who is basically bad.
