What is Macbeth referring to when she says to doubt the equivocation of the fiend?

Answer 1

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Answer 2

I see that in your production you have cast Macbeth with a woman. That's interesting. (otherwise you must say "he says" not "she says")

The quotation you are referring to is:

If thou speak'st false,

Upon the next tree shalt thou hang alive,

Till famine cling thee: if thy speech be sooth,

I care not if thou dost for me as much.

I pull in resolution, and begin

To doubt the equivocation of the fiend

That lies like truth: 'Fear not, till Birnam wood

Do come to Dunsinane:' and now a wood

Comes toward Dunsinane.

He's speaking to a messenger who has just told him that Birnam wood is coming to Dunsinane, an event about which he said, earlier in the play, "That can never be!" As the passage clearly shows, he says that if the messenger is telling the truth, he cannot rely on the prophecy "fear not, till Birnam wood do come to Dunsinane", because it is "equivocation"--it seems to say one thing and means another. And who is the "fiend that lies like truth"? You'll need three guesses because there were three of them around that cauldron.