What are some quotes of dramatic significance from Macbeth?
“This castle hath a pleasant seat; the air/ Nimbly and sweetly recommends itself/ Unto our gentle senses”
Duncan says this just as he's entering Macbeth's castle. The dramatic significance could be how much danger he's in but has no idea of, like a lamb to the slaughter
Your quote by Duncan is from Act 1, scene 6. A similar quote by Duncan is as follows: "There's no art to find the mind's construction in the face" (1.4). He is speaking of the traitorous Thane of Cawdor in whose face he couldn't read betrayal. Yet he doesn't realize how true his statement is and how much it will come to haunt him: he won't see Macbeth's traitorous plans in his face either.
Duncan also says of the original Thane of Cawdor: "He was a gentleman on whom I built/An absolute trust" (1.4). This lets the audience know that Duncan's trust will ironically be betrayed by two Thanes of Cawdor: he fully trusted the first as he will do with Macbeth.
A quote from Macbeth is as follows: "Stars, hide your fires;/Let not light see my black and deep desires:.." (1.4) This quote lets the audience know, for the first time, that the witches' prophesy has affected Macbeth so much that he is contemplating a black desire. This is a small hint to the murder plot that will soon unfold.
One of my personal favorites is by the Second Witch:
By the pricking of my thumbs,
Something wicked this way comes.
Macbeth enters after this, which indicates that Macbeth has indeed become "something wicked" (Act IV, scene i). The dramatic significance relates to characterization: Macbeth embodies wickedness as conjured by the Witches and has become the emblem of the power of fate.