ambition

Macbeth's relentless pursuit of the throne, fueled by the witches' prophecy and Lady Macbeth's encouragement, is a central driving force in the play. This ambition leads him down a path of violence and betrayal

"I have no spur to prick the sides of my intent, only vaulting ambition"

reveals Macbeth's internal conflict. He admits his only motivation for murdering Duncan is his ambition, which he recognizes as a dangerous and reckless drive. 

"Stars, hide your fires! Let not light see my black and deep desires"

showcases macbeths desire for power and the length he is willing to go to, even to the point of wanting to hide his evil intentions

Two truths are told, As happy prologues to the swelling act of this imperial theme

uttered after hearing the witches' prophecy, shows Macbeth's immediate anticipation of becoming king, demonstrating his eagerness for power

“This have i thought good to deliver thee (my dearest partner of greatness) what greatness i promis’d thee’

written in the letter, LM will become queen, macbeth understands LM ambition is greater than his own, wants to use lady macbeth so he can rise to the throne

"All hail, Macbeth, thou shalt be king hereafter!"

spoken by the witches, initially seems to fulfill Macbeth's ambition, but it also sets the stage for the tragic consequences to come