In this scene Macbeth’s wife talks to him.  She has read his letter, telling her about the good news that he heard from the witches, and she wants to make sure that he acts quickly in order to become king.

It’s hard to know exactly how Macbeth feels about the news, however.  In scene 3, he has several different asides that vary in emotion from elation (“The greatest is behind”) to horror (“let light not see my black and deep desires”).  I’m not sure of what Macbeth wants to do at this point, but my sense is that he has very strong reservations against killing his King. 

The question, then, is what he wants from Lady Macbeth:  Did he send the letter in hopes that SHE would get excited about becoming queen and talk him into committing the murder that he is afraid to commit?  Or did he send it innocently?  Does he really want to be pushed into action, or does he already know what he wants to do?

In the following passage, I am inventing a subtext for Macbeth that suggests that he can’t stand his wife, and just wants to go on living as he is (perhaps without having his crazy, nagging wife around).  This interpretation is unlikely, but I hope will get a few (cheap) laughs.  Enjoy:

Great Glamis! worthy Cawdor!
Greater than both, by the all-hail hereafter!
Thy letters have transported me beyond
This ignorant present, and I feel now
The future in the instant.

MACBETH

Oh God, why did I send that stupid letter?!  Now I have to deal with my wife nagging me about killing Duncan!  Ugh.

My dearest love,
Duncan comes here to-night.

WHAT?  Why did I just say that?  Now she’s going to bug me even more.  When will I learn?!

LADY MACBETH

And when goes hence?

MACBETH

To-morrow, as he purposes.

Great.  Here it comes… she’s going to start talking about murder.

LADY MACBETH

O, never
Shall sun that morrow see!

See… I knew it.

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.

MACBETH

I knew it!!!  What can I say to get this crazy wife off of my back? 

We will speak further.

LADY MACBETH

Only look up clear;
To alter favour ever is to fear:
Leave all the rest to me.

Yeah, whatever… I’m never getting out of this.  At least I didn’t tell her that I’d clean out the moat…