How do Macbeth and Banquo react to the experience after the weird sisters vanish? (Act 1, scene 3)

In Shakespeare's play Macbeth,
Macbeth and Banquo have very different reactions to the visitation of the three
witches.

Macbeth is entranced by what the witches have told
him. He becomes preoccupied with imagining what the weird sisters' words might
ultimately mean to him. Becoming Thane of Cawdor would be nice, but becoming King is
unimaginable—or has been up to this point.

Banquo, also a
great warrior and Macbeth's good friend, is very different. He is cautious with regard
to the witches' words: he asks for his prediction, but tells them he does not fear them
and he will not beg. He expresses no deep longing, but perhaps only
curiosity.

When the witches' first prophecy comes true,
Banquo is shocked:

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What, can the Devil speak
true?

(Elizabethans believed
the Devil could not speak words that were true.) Banquo is cautious and tells Macbeth he
should be cautious as well.

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...'Tis strange; / And oftentimes to win us to
our harm, / The instruments of darkness tell us truths, / Win us with honest trifles, to
betray's / In deepest
consequence.

The words mean
that sometimes evil can trick us with something small, like getting the title to Cawdor,
but then lead us do something awful later, because we believed the first little
prediction that came true.

Macbeth has little doubt after
the witches' predictions, especially when he receives his new title, but Banquo
exercises caution and counsels Macbeth to do the same.