Analysis for "two truths are told... but what is not" speech

Macbeth's speech (Act 1, scene 3, lines 128-142) is very important to the play's plot. This is because of three reasons. Firstly, the first truth is told from the witches' prophecies. Secondly, this extract shows Macbeth's reaction to the first prophecy coming true in his thoughts. Lastly, his speech shows the start of Macbeth's vaulting ambition.
The three witches revealed to Macbeth that he will soon become the Thane of Cawdor, and later onwards, the King. You see the plot slowly advancing when Macbeth is pronounced Thane of Cawdor by Ross and Angus, Kind Duncan's messengers, ("happy pr…