Macbeth uses a clothing metaphor to ask why he is getting a title he doesn’t deserve (foreshadow of getting other titles he doesn’t deserve like king?)

“That trusted home
Might yet enkindle you unto the crown,
Besides the thane of Cawdor. But '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.”

Banquo warns of the dangers of trusting such a prophesy 

He believes that what seems to make us happiest often lead to our downfall

[Aside] Two truths are told,
As happy prologues to the swelling act
Of the imperial theme.--I thank you, gentlemen.

Cannot be ill, cannot be good: if ill,
Why hath it given me earnest of success,
Commencing in a truth? I am thane of Cawdor:
If good, why do I yield to that suggestion
Whose horrid image doth unfix my hair
And make my seated heart knock at my ribs,
Against the use of nature?

Right away, Macbeth is already considering murder; he is not following Banquo’s warnings and jumps right in

There's no art
To find the mind's construction in the face:
He was a gentleman on whom I built
An absolute trust.

Duncan speaks of his trust of the former Thane of Cawdor; this is ironic because this is exactly what happens with Duncan and Macbeth: Duncan trusts Macbeth and Macbeth betrays that trust 

The service and the loyalty I owe,
In doing it, pays itself. Your highness' part
Is to receive our duties; and our duties
Are to your throne and state children and servants,
Which do but what they should, by doing ever thing
Safe toward your love and honour.

Macbeth is telling the king that he owes him for everything he (the king) has done for him(Macbeth). This is one of the factors that almost makes Macbeth chicken out of killing Duncan. It is almost iron that he says this, because Macbeth is saying it is his duty to do things for the king and protect him, but he ends up killing him.

Welcome hither:
I have begun to plant thee, and will labour
To make thee full of growing. Noble Banquo,
That hast no less deserved, nor must be known
No less to have done so, let me enfold thee
And hold thee to my heart.

Duncan: You are welcome here. By making you thane of Cawdor, I have planted the seeds of a great career for you, and I will make sure they grow. (to BANQUO) Noble Banquo, you deserve no less than Macbeth, and everyone should know it. Let me bring you close to me and give you the benefit of my love and good will.

Aside] The Prince of Cumberland! that is a step
On which I must fall down, or else o'erleap,
For in my way it lies. Stars, hide your fires;
Let not light see my black and deep desires:
The eye wink at the hand; yet let that be,
Which the eye fears, when it is done, to see.

After Duncan tells that his son Malcolm will succeed him, Macbeth says that he will have to either find a way around him or give up. Macbeth asks his eyes to not show his inner thoughts, because what he is thinking about doing/will do is too horrible to be known or seen.

Glamis thou art, and Cawdor; and shalt be
What thou art promised: yet do I fear thy nature;
It is too full o' the milk of human kindness
To catch the nearest way: thou wouldst be great;
Art not without ambition, but without
The illness should attend it: what thou wouldst highly,
That wouldst thou holily; wouldst not play false,
And yet wouldst wrongly win: thou'ldst have, great Glamis,
That which cries 'Thus thou must do, if thou have it;
And that which rather thou dost fear to do
Than wishest should be undone.' Hie thee hither,
That I may pour my spirits in thine ear;
And chastise with the valour of my tongue
All that impedes thee from the golden round,
Which fate and metaphysical aid doth seem
To have thee crown'd withal.

In this quote, Lady Macbeth finishes reading the letter sent from Macbeth, and sees that he has potential to be great, but only if he hardens himself and does the deed. She is frightened he does not have what it takes to follow through.

Come, you spirits
That tend on mortal thoughts, unsex me here,
And fill me from the crown to the toe top-full
Of direst cruelty! make thick my blood;
Stop up the access and passage to remorse,
That no compunctious visitings of nature
Shake my fell purpose, nor keep peace between
The effect and it! Come to my woman's breasts…

Lady Macbeth is asking to be made like a man so she can have the ability to kill the king herself. This relates to the gender theme that is evident throughout the play: She cannot be a woman and do something as horrible as killing at the same time.

O, never
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;

Lady Macbeth is frightened that when the king arrives Macbeth will give everything away with his face. She tells him he has to be able to hide his true emotions for now, and strike later when it is least expected. She tells Macbeth to relax and she will handle all the preparations. This is ironic because later on she and Macbeth have a role reversal, and he won’t even tell her is plan, and just says don’t worry about it because he has it under control.

He's here in double trust;
First, as I am his kinsman and his subject,
Strong both against the deed; then, as his host,
Who should against his murderer shut the door,
Not bear the knife myself. Besides, this Duncan
Hath borne his faculties so meek, hath been
So clear in his great office, that his virtues
Will plead like angels, trumpet-tongued, against
The deep damnation of his taking-off;
And pity, like a naked new-born babe,
Striding the blast, or heaven's cherubim, horsed
Upon the sightless couriers of the air,
Shall blow the horrid deed in every eye,
That tears shall drown the wind. I have no spur
To prick the sides of my intent, but only
Vaulting ambition, which o'erleaps itself
And falls on the other.

Macbeth starts thinking about the reasons he should not kill Duncan: they are cousins, Duncan trusts him, he is Duncan’s host, Duncan has done nothing wrong, etc. He is worried that such ambition will only end badly for him. This represents the time in his life when Macbeth still thought about actions before actually doing them.

We will proceed no further in this business:
He hath honour'd me of late; and I have bought
Golden opinions from all sorts of people,
Which would be worn now in their newest gloss,
Not cast aside so soon.

Macbeth decides not to kill Duncan just yet. He wants to keep his new clothes shiny and new for a bit longer. 

When you durst do it, then you were a man;
And, to be more than what you were, you would
Be so much more the man. Nor time nor place
Did then adhere, and yet you would make both:
They have made themselves, and that their fitness now
Does unmake you. I have given suck, and know
How tender 'tis to love the babe that milks me:
I would, while it was smiling in my face,
Have pluck'd my nipple from his boneless gums,
And dash'd the brains out, had I so sworn as you
Have done to this.

Lady Macbeth exhibits how for the time being she is very unladylike. She would be willing to kill her own child if she had promised Macbeth she would do so. She wants Macbeth to step up and “be a man” and just kill Duncan already. (Kind of a reversal of the gender roles theme)

There's one did laugh in's sleep, and one cried
'Murder!'
That they did wake each other: I stood and heard them:
But they did say their prayers, and address'd them
Again to sleep.

Macbeth is talking about how Duncan’s aids were “talking in their sleep” when he was killing Duncan. This foreshadows that Macbeth has “murdered sleep”, specifically Lady Macbeth’s. Later on, she is no longer able to sleep easily and innocently, but rather she is plagued by disturbing dreams and a guilty conscience. 

Infirm of purpose!
Give me the daggers: the sleeping and the dead
Are but as pictures: 'tis the eye of childhood
That fears a painted devil. If he do bleed,
I'll gild the faces of the grooms withal;
For it must seem their guilt.

Lady Macbeth is mocking Macbeth’s masculinity. She is saying that dead bodies are no scarier than pictured. She says he has to get over his fear. She will go put the daggers in their hands, because it has to look like they did it.

Whence is that knocking?
How is't with me, when every noise appalls me?
What hands are here? ha! They pluck out mine eyes.
Will all great Neptune's ocean wash this blood
Clean from my hand? No, this my hand will rather
The multitudinous seas in incarnadine,
Making the green one red.

Macbeth realizes what he has done will have a profound effect on others. If he washes his hands in a sea, rather than cleaning his hands, he will turn the entire ocean the color of blood. His wrongdoings will spread and infect the entire kingdom.

My hands are of your colour; but I shame
To wear a heart so white. Knocking within. I hear a knocking
At the south entry: retire we to our chamber;
A little water clears us of this deed:
How easy is it, then! Your constancy
Hath left you unattended. Knocking within

Hark! more knocking.
Get on your nightgown, lest occasion call us,
And show us to be watchers. Be not lost
So poorly in your thoughts.

This quote shows that Lady Macbeth has not changed yet. Macbeth is still more hesitant, nervous, and tormented by the situation, while she still has no remorse and is unphazed by what has happened. 

Had I but died an hour before this chance,
I had lived a blessed time; for, from this instant,
There's nothing serious in mortality:
All is but toys: renown and grace is dead;
The wine of life is drawn, and the mere lees
Is left this vault to brag of.

Macbeth is putting on a show of being sad about the death of Duncan. He is saying that he would have been happy if he lived until just before the death of Duncan. Without Duncan, life is basically empty.

To be thus is nothing;
But to be safely thus.--Our fears in Banquo
Stick deep; and in his royalty of nature
Reigns that which would be fear'd: 'tis much he dares;
And, to that dauntless temper of his mind,
He hath a wisdom that doth guide his valour
To act in safety. There is none but he
Whose being I do fear: and, under him,
My Genius is rebuked

Macbeth is saying that the only person he is really scared of is Banquo because he is smart and brave. He is saying it’s not worth being king if he can’t appreciate all the aspect of being king without worry. At this point, Macbeth makes the decision that Banquo will have to be murdered to protect his crown.

There's comfort yet; they are assailable;
Then be thou jocund: ere the bat hath flown
His cloister'd flight, ere to black Hecate's summons
The shard-borne beetle with his drowsy hums
Hath rung night's yawning peal, there shall be done
A deed of dreadful note.

“What's to be done?”

Be innocent of the knowledge, dearest chuck,

Till thou applaud the deed. Come, seeling night,

Scarf up the tender eye of pitiful day

Macbeth and Lady Macbeth have switched roles. At first, she was the one who always planned everything and didn’t fill him in until it was necessary. Now, he is doing the same thing to her. He is becoming less human, and she is becoming more womanly and more human.

Then comes my fit again: I had else been perfect,
Whole as the marble, founded as the rock,
As broad and general as the casing air:
But now I am cabin'd, cribb'd, confined, bound in
To saucy doubts and fears. But Banquo's safe?

Macbeth killed Duncan as the ultimate act of freedom, but now Macbeth feels less and less free. He has been confined by his own acts.

O proper stuff!
This is the very painting of your fear:
This is the air-drawn dagger which, you said,
Led you to Duncan. O, these flaws and starts,
Impostors to true fear, would well become
A woman's story at a winter's fire,
Authorized by her grandam. Shame itself!
Why do you make such faces? When all's done,
You look but on a stool.

Lady Macbeth says this when Macbeth says he saw Banquo’s ghost at the banquet. Sheis tearing down his masculinity and telling him he looks stupid. She doesn’t yet believe in the retributions associated with their actions. Macbeth still feels guilt, while she does not feel any yet.

Time, thou anticipatest my dread exploits:
The flighty purpose never is o'ertook
Unless the deed go with it; from this moment
The very firstlings of my heart shall be
The firstlings of my hand. And even now,
To crown my thoughts with acts, be it thought and done:
The castle of Macduff I will surprise;

Macbeth starts to become lass human: he will no longer think about his actions, he will just do them. The first thing in his head is the first thing his hands will do.

I have lived long enough: my way of life
Is fall'n into the sear, the yellow leaf;
And that which should accompany old age,
As honour, love, obedience, troops of friends,
I must not look to have; but, in their stead,

Curses, not loud but deep, mouth-honour, breath,
Which the poor heart would fain deny, and dare not.

Macbeth realizes that since he is not confined by time and place, which is what he wanted, he cannot enjoy the “fruits” of such like friends, honor, and love. He is king, but this menas very little if he cannot have all the good things associated with being king.

I have almost forgot the taste of fears;
The time has been, my senses would have cool'd
To hear a night-shriek; and my fell of hair
Would at a dismal treatise rouse and stir
As life were in't: I have supp'd full with horrors;
Direness, familiar to my slaughterous thoughts
Cannot once start me.

When Macbeth hears a scream, he says this: he has seen and done so many horrible things that it doesn’t even phase him anymore. This shows Macbeth becoming less and less human with the passing of time. 

She should have died hereafter;
There would have been a time for such a word.
To-morrow, and to-morrow, and to-morrow,
Creeps in this petty pace from day to day
To the last syllable of recorded time,
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player
That struts and frets his hour upon the stage
And then is heard no more: it is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.

Macbeth says this after he hears of the death of his wife. He has been so hardened by all the horrible things he has done that the death of his wife does not even phase him. He is basically saying that life has no meaning, and this almost justifies his actions because then they are not important anymore. 

They have tied me to a stake; I cannot fly,
But, bear-like, I must fight the course. What's he
That was not born of woman? Such a one
Am I to fear, or none.

This shows Macbeth’s descent to being almost non-human. He is like a bear. He is less human, and more like animal. 

Out, damned spot! out, I say!--One: two: why,
then, 'tis time to do't.--Hell is murky!--Fie, my
lord, fie! a soldier, and afeard? What need we
fear who knows it, when none can call our power to
account?--Yet who would have thought the old man
to have had so much blood in him.

Lady Macbeth says this while she is sleepwalking. It shows how her role has somewhat reversed. Before, when Macbeth first killed Duncan, she could sleep soundly, and told him that a little water would wash away the blood.  Now, she is starting to go a little crazy, and can’t sleep, sees blood, and feels guilt. This ties into the gender theme: women cannot be evil (at least not for too long).

We shall not spend a large expense of time
Before we reckon with your several loves,
And make us even with you. My thanes and kinsmen,
Henceforth be earls, the first that ever Scotland
In such an honour named. What's more to do,
Which would be planted newly with the time,
As calling home our exiled friends abroad
That fled the snares of watchful tyranny;
Producing forth the cruel ministers
Of this dead butcher and his fiend-like queen,
Who, as 'tis thought, by self and violent hands
Took off her life; this, and what needful else
That calls upon us, by the grace of Grace,
We will perform in measure, time and place:
So, thanks to all at once and to each one,
Whom we invite to see us crown'd at Scone.

Malcolm says that now that he is king, he will begin to fix everything. He will readjust place by calling everyone home from England, and all the other places they went to escape Macbeth. He will do everything at the right time as well. Malcolm realizes that thus is the making of a good king: one who operates in the proper time and place. 

“Be comforted:
Let's make us medicines of our great revenge,
To cure this deadly grief.”
“He has no children. All my pretty ones?
Did you say all? O hell-kite! All?
What, all my pretty chickens and their dam
At one fell swoop?”
“Dispute it like a man.”
“I shall do so;
But I must also feel it as a man.”