How we cite our quotes:
My dearest love,
Duncan comes here to-night.
And when goes hence?
To-morrow, as he purposes.
Shall sun that morrow see!
Your face, my thane, is as a book where men
May read strange matters. To beguile the time,
Look like the time; bear welcome in your eye,
Your hand, your tongue: look like the innocent flower,
But be the serpent under't. He that's coming
Must be provided for: and you shall put
This night's great business into my dispatch;
Which shall to all our nights and days to come
Give solely sovereign sway and masterdom. (1.5.4)
Yeah, King Duncan is not getting out of this castle alive. What caught our attention about this passage is the way the couple talks about the planned murder in terms of time —"Duncan comes here to-night"; "when goes he hence"; "never / Shall sun that morrow see!" The pair talk about their plans as though time will come to a complete halt for King Duncan. Lady Macbeth also puns on the word "time" when she suggests Macbeth should suit his demeanor to the occasion ("To beguile the time, / Look like the time") in order to make Duncan believe he's happy to see him.
If it were done when 'tis done, then 'twere well It were done quickly: if the assassination Could trammel up the consequence, and catch With his surcease success; that but this blow Might be the be-all and the end-all here, But here, upon this bank and shoal of time, We'ld jump the life to come. (1.7.1)
Even if Macbeth isn't caught after he murders King Duncan, he'll be punished in the afterlife (the "life to come"). So why does he decide that temporary, earthly power is worth eternal damnation?
Hang out our banners on the outward walls; The cry is still 'They come:' our castle's strength Will laugh a siege to scorn: here let them lie Till famine and the ague eat them up: Were they not forced with those that should be ours, We might have met them dareful, beard to beard, And beat them backward home. (5.5.1)
Macbeth's strategy during the siege is to hole up in the palace and bide his time "till famine and the augues" (starvation and illness) destroy the enemy soldiers. What's creepy about this is that he's still acting like he has all the time in the world, when in fact his borrowed time is just about up. (Fun fact: plays are bound by time in the way that other works of literature aren't. You can read a novel as fast or as slowly as you want, but when you're watching a play you only get the amount of time that a director has assigned. Almost—we're just saying—as though you're being controlled by fate.)