Good answer, kkganey! I would agree that it is the first prophesy, made in Act I, scene iii. This, considering how a tragedy is structured, simply must be true. The action must be ignited in the first Act of the play, and the tragic hero must have his "call to action" presented to him in this first Act as well. And just to be clear, technically speaking, this is also the only prophesy made by the Witches themselves. The Act IV prophesies are not made by the Witches, but by the apparitions that they conjure.
In Act One of Macbeth, Macbeth has just gained the favor of King Duncan by performing well and faithfully in the battle against the insurgents. Macbeth seems to be headed for one course of action (loyal and brave service to his King), but when he meets the Witches and hears their prophesy for his future, things begin to change. And it is actually the confirmation of the first part of their prophesy -- that Macbeth will become Thane of Cawdor -- that pushes Macbeth to consider how the second part -- that he will be King -- could be fulfilled.
This prophesy is the stick needed to prod the sleeping "tragic flaw" in Macbeth awake, his ambition, and goad him forward to the actions that seal his own demise -- the murders of Duncan, Banquo and Macduff's family -- all in service to the ambition begun at the mention of the Witches prophesy in Act I.
For more on Act I, scene iii and Macbeth's transformation "From 'Brave Macbeth' to 'Dead Butcher,' " please follow the links below.
To me, the most important prophecy of the tale is the witches' prophecy in Act I hailing Macbeth as King. This prophecy leads to the following:
- Macbeth's thoughts of regicide -the killing of a royal-
- His writing to Lady Macbeth
- Lady Macbeth's plan to kill Duncan
- the start of the ambition
- the connection to the witches
- the turning point in Macbeth's life (**not in the play)
- Macbeth's drive to the throne
- Macbeth's dependence on the witches' prophecies
you can not make any responce to any individual's favour,i personally think that the all three witches have very significance role in herself
Whilst prophecy 1 was to get his attention 'hail Macbeth, thane of Glamis'' the second to show that actually what they said could hold some truth, 'thane of Cawdor' it was the third prophecy King hereafter' that caused Macbeth to ponder on becoming King and consequently tell Lady M what had happened, she pushes him into action and he kills Duncan, this results in him becoming King. The first half of the play is thus advanced by this prophecy.
The second half of the play is all a consequence of Macbeth allowing himself to be influenced by this prophecy. He orders Banquos execution because he is afraid he will be usurped by Fleance. He goes to the witches a second time out of fear and the second lot of prophecies ( which are deliberately vague) cause the outcome at the end of the play. Killing MacDuffs family, holding up in Dunsinane and facing MacDuff's army without fear. However, were it not for the prophecy 'thou shalt be King Hereafter' there would be no action in this play.