In Shakespeare's Macbeth, Act Two, scene two, finds the characters of Macbeth and Lady Macbeth reversed—in terms of what a reader might expect from a valiant and seasoned warrior (such as Macbeth) and his wife (who one might believe to be the "gentler sex").
Macbeth has committed the murder, but though death is not new to him, the taking of an innocent life is. He is so shaken up that he hears things, jumps at every sound and refuses to take the murder weapons back to Duncan's room. The very items that will prove their treason Macbeth will not touch—he is more upset by facing the reality of what he has done than worried about being caught. Lady Macbeth tells her husband to pull himself together and put the daggers back. Macbeth responds:
I'll go no more:
I am afraid to think what I have done;
Look on't again I dare not. (64-66)
Ironically, Lady Macbeth has only become more aggressive as the plan to take the throne progresses. First she notes that if he hadn't looked like her father, she would have killed him herself, while he was sleeping.
Had he not resembled
My father as he slept, I had done't. (15-16)
Lady Macbeth will eventually berate her husband for his squeamishness, but first she tries to reason with him:
Consider it not so deeply. (40)
She says to refrain from obsessing over it: it will drive them crazy...
These deeds must not be thought
After these ways; so, it will make us mad. (45)
By the time Macbeth refuses to return the daggers, Lady Macbeth is furious. She has no time for his whining and whimpering. She shows herself to be very much at ease with the taking of Duncan's life. She is truly heartless as she grabs the weapons and tells her husband that she will return them—that the dead are nothing to be afraid of! If that is not enough, Lady Macbeth will also spread the King's blood on the guards, for when the castle wakes in the morning, it must appear as if Duncan's guards murdered him while he slept. She rails at Macbeth, saying...
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. (67-72)
Macbeth's guilt is apparent: symbolically, the extent of the evil in what he has done is so abhorrent to him, that he believes the blood on his hands is damning enough that he could turn the seas red if he washed his hands in the ocean waters. Lady Macbeth sneers at him: she notes that she is just as guilty—her hands are just as bloody...but she isn't falling apart.
By the time the knocking at the gate sounds (as Macduff arrives to depart with the King), Macbeth is wishing he had never committed the act:
Wake Duncan with thy knocking! I would thou couldst! (93)
Lady Macbeth has no such misgivings—she is a woman without feeling, while Macbeth is not as strong as might have been expected.