I fight
Of treasonous malice.

His solemn language here reminds us of his grave words about 'the
instruments of darkness,' and of his later prayer to the 'merciful
powers.' He is profoundly shocked, full of indignation, and determined
to play the part of a brave and honest man.

But he plays no such part. When next we see him, on the last day of his
life, we find that he has yielded to evil. The Witches and his own
ambition have conquered him. He alone of the lords knew of the
prophecies, but he has said nothing of them. He has acquiesced in
Macbeth's accession, and in the official theory that Duncan's sons had
suborned the chamberlains to murder him. Doubtless, unlike Macduff, he
was present at Scone to see the new king invested. He has, not formally
but in effect, 'cloven to' Macbeth's 'consent'; he is knit to him by 'a
most indissoluble tie'; his advice in council has been 'most grave and
prosperous'; he is to be the 'chief guest' at that night's supper. And
his soliloquy tells us why:

Thou hast it now: king, Cawdor, Glamis, all,
As the weird women promised, and, I fear,
Thou play'dst most foully for't: yet it was said
It should not stand in thy posterity,
But that myself should be the root and father
Of many kings. If there come truth from them--
As upon thee, Macbeth, their speeches shine--
Why, by the verities on thee made good,
May they not be my oracles as well,
And set me up in hope? But hush! no more.

This 'hush! no more' is not the dismissal of 'cursed thoughts': it only
means that he hears the trumpets announcing the entrance of the King and
Queen.

His punishment comes swiftly, much more swiftly than Macbeth's, and
saves him from any further fall. He is a very fearless man, and still so
far honourable that he has no thought of acting to bring about the
fulfilment of the prophecy which has beguiled him. And therefore he has
no fear of Macbeth. But he little understands him. To Macbeth's
tormented mind Banquo's conduct appears highly suspicious. _Why_ has
this bold and circumspect[237] man kept his secret and become his chief
adviser? In order to make good _his_ part of the predictions after
Macbeth's own precedent. Banquo, he is sure, will suddenly and secretly
attack him. It is not the far-off accession of Banquo's descendants that
he fears; it is (so he tells himself) swift murder; not that the 'barren
sceptre' will some day droop from his d