We have scotch'd the snake, not kill'd it:
She'll close and be herself, whilst our poor malice Remains in danger of her former tooth.... Ere we will eat our meal in fear and sleep In the affliction of these terrible dreams That shake us nightly: better be with the dead, Whom we, to gain our peace, have sent to peace,
Than on the torture of the mind to lie
In restless ecstasy. Duncan is in his grave; After life's fitful fever he sleeps well; Treason has done his worst: nor steel, nor poison, Malice domestic, foreign levy, nothing, Can touch him further.
While Lady Macbeth appears to be looking back at the previous murder, Macbeth looks forward, anticipating the next murder, of which Lady Macbeth is not yet fully aware. That distinction between their two states of knowledge allows Shakespeare to play once more on the power relationship between husband and wife. Here, then is yet another reversal of character, and it is shown in two major ways: first, by Lady Macbeth's innocent-sounding questions and, second, by Macbeth's adoption of animal imagery. In Act I, Scene 5, Lady Macbeth was the one who spoke of "the raven" and "the serpent." Now Macbeth takes on the same language of horror, imagining his mind to be "full of scorpions," and speaking of the "bat" and the "shard-born (dung-bred) beetle."