Banquo

Banquo says, What, can the devil speak true? Banquo knows that nothing good can come from the witch's prophesies. He tries to warn Macbeth that no matter how good the witch's news sounds, they will betray him in the end. That's simply what witches do,

That, trusted home,
Might yet enkindle you unto the crown,
Besides the thane of Cawdor. But ’tis strange.
And oftentimes, to win us to our harm,
The instruments of darkness tell us truths,
Win us with honest trifles, to betray ’s
In deepest consequence.