macbeth gets the prophecies from the witches
"all hail macbeth! hail to thee, thane of Glamis... thane of Cawdor... that shalt be king hereafter"
the witches ability to foresee macbeths future and bestow titles upon him that he does not yet possess
the prophecies create a sense of fate and destiny implying that supernatural forces are at play
they serve as a catalyst for the events of the play highlighting the power and influence of the supernatural on human actions and outcomes