In act 1 the down fall of Macbeth is already foreshadowed from the very first scene as "instruments of darkness" are having a discussion about him hinting on how they are going to "tempest-toss" him just like the other men that they have delt with
"thunder, lighting, or in rain"
"fair is foul and foul is fair "
"unseamed him from the nave to the chap"
"my dearestpartner of greatness"
"he will be what he has been promised "
"that i may pour my spirits into his ear "
"unsex me here "
"look like the innocent flower but be the serpent under it "
"bought him golden opinions"
"stars hide you fire, let light not see my dark and deep desires"