MACDUFF: I am not treacherous.
MALCOLM: But Macbeth is.
A good and virtuous nature may recoil
In an imperial charge.
– William Shakespeare
Macbeth, Act 4, Scene 3. Macduff is forced to defend himself when Malcolm questions his loyalty and reminds him of his friendship with Macbeth. Despite Macduff’s protest that he is not treacherous, Malcolm is still not convinced. He says that a good man may turn bad at the command of a forceful king like Macbeth.