In Macbeth, Shakespeare shows how the witches' prophecies, Lady Macbeth's desire for power, and Macbeth's yearning to be king, affect the fate of the play.
In Act I, the witches' chant show how Shakespeare gives the fate of Macbeth, "Thane of Glamis", "Thane of Cawdor", "that shalt be King hereafter".( Act 1 scene 3, lines 48-50) He has no other choice, but to believe them because there first two predictions were true. They call him the Thane of Glamis, which he is at the present time. Then they call him Thane of Cawdor, which he finds out shortly after that he is the new Thane of Cawdor. Lastly they call him King hereafter, which he realizes is his fate. Macbeth sees this fate in his eyes to be very unlikely and almost impossible because of the current circumstances. His reaction to the witches is "stands not within the prospect of belief"( Act 1 scene 3, line 74), which tells the reader that the witches' prophecies are a far reach from reality.
Macbeth begins to think if he ever had the chance to become king that it would be a great honor that he would accept, "If chance will have me King, why, chance may crown me".(Act 1 scene 3, line 143) The prophecy of Banquo's son having power in the future effects the actions of Macbeth later in the play too. The thought that Banquo's child might take over the thrown from Macbeth makes him feel the need to get rid of him. Fleance, Banquo's son, gets scared as his father is being killed and flees, "Fly, good Fleance, fly, fly, fly!".( Act3 scene 3, line 18) After his talk with the witches Macbeth starts to think about their predictions, and how he will have to kill the king. This frightens Macbeth to think about killing his great king, so he decides to let fate lead him into the future.
Lady Macbeth actions play a huge role in the fate of play by pushing him into killing the king. The instant she reads the letter from her husband that explains the prophecies Lady Macbeth wants to make her husband kill the king, "to catch the nearest way. Thou wouldst be great"(Act 1 scene 5, line 13). This shows the evil ways of Lady Macbeth and her selfishness. She does not care if her husband would be in danger when trying to kill Duncan, but what she would be able to do if she were queen. She knows the weaknesses of her husband and how she can manipulate him into what she wants, " It is too full o' the milk of human kindness"( Act 1 scene 5, line 12). She figures if he kills Duncan that she will become queen and have all the power she wants. One of her ways to make Macbeth kill the king is when she tells him that he needs to in order to be a real man, " Be so much more the man"(Act 1 scene 7 line 51). She also plays a big role in the actual murders by drugging the guards so Macbeth can get into the room to kill Duncan.
From the start Macbeth knew that in order to be king he had to kill Duncan. Macbeth told himself that his only reason for killing Duncan was his ambition, which went against all the good things that Duncan stood for, "but only vaulting ambition"(Act 1 scene 7, line 27). He also knew that this was his fate and what had to be done would be done. Even though Macbeth is pushed to kill the king by his wife it still comes down to the fact that he wants the power. It was Macbeth's choice to kill Duncan from the start to the end. He could of turned back whenever he wanted, but he truly wanted to murder the king and take over the thrown. After the murder there are many other conflicts that Macbeth comes across to fulfill his fate. He needs to kill the two grooms that were drugged up when Macbeth went in the room of Duncan, "Steeped in the colors of their trade"(Act 2 scene 3, line 103).He never expected to even kill Duncan, and he ends up killing many other people. He went from an innocent man to a mass murderer. There is no reason for these actions of Macbeth except the fact that he was destined from the start of the play to perform all these actions.