| Quote #1
The audience might not get a look at the stage directions, but all the clues are here: the women speak in rhythmic, chant-like lines (check out "Writing Style" for a close look at their language); they call out to their familiars—and, since "Graymalkin" was a common name for a cat, the audience would have gotten the reference, sort of like saying, "I come, Crookshanks/ Hedwig calls"; and, finally, they end with that creepy inversion: fair is foul, and foul is fair." Supernatural? Super creepy, at least.
| Quote #2
First Witch I will drain him dry as hay: Sleep shall neither night nor day Hang upon his pent-house lid; He shall live a man forbid: Weary se'nnights nine times nine Shall he dwindle, peak and pine: Though his bark cannot be lost, Yet it shall be tempest-tost. Look what I have. (1.3.2)
All the sailor's wife did was refuse to share her chestnuts, and now the sisters are going to make him impotent and infertile. You do not want to tick off a witch. (Oh, but those chestnuts? Sometimes a chestnut isn't just a chestnut, if you know what we mean.)
| Quote #3
BANQUO That look not like the inhabitants o' the earth, And yet are on't? Live you? or are you aught That man may question? […] You should be women, And yet your beards forbid me to interpret That you are so. (1.3.1)
If Macbeth were a horror movie—which it kind of is—then Banquo would be the skeptic who gets killed because he refuses to believe. Where Macbeth accepts the supernatural unquestioningly, doing some pretty dumb things like following a floating dagger and arguing publically with a ghost, Banquo isn't to completely discard his reason and rationality. Unfortunately, that turns out to be the wrong choice.