Why is Macbeth afraid of Banquo although they were ultimate friends?also tell the comparison in personality of both characters from Macbeth.

Macbeth is afraid of Banquo and rightly so. Banquo heard
the witches' prophecy. Macbeth fears that Banquo will suspect him if he murders King
Duncan. Since Banquo heard the prophecy that Macbeth would be king, Banquo may suspect
that Macbeth has indeed murdered King Duncan to claim his position as
king.

After the murder of King Duncan is announced, Banquo
does indeed suspect foul play. In Act three, Scene one, speaking only to himself, he
states that Macbeth now has it all:

readability="13">

You have it now, King, Cawdor, Glamis,
all,
As the weird women promised; and, I’m afraid,
You played most
foully for it.

Indeed, Banquo
is a threat. He suspects that Macbeth has murdered King Duncan. Now, Macbeth cannot rest
knowing Banquo suspects him. In Act three, Scene two, Macbeth is having terrible
nightmares, and Banquo is part of the reason that Macbeth cannot
sleep:

We
have crushed the snake, but we haven’t killed it;
She'll recover, and be
herself, while our poor evil-doing
Remains in danger of her poisonous
bite.
Only let the order of the universe be disrupted,
Both the real
and spiritual worlds suffer,
Before we will eat our meal in fear, and
sleep
In the affliction of these terrible dreams
That wake us up
nightly. It’s better to be with the dead,
Whom we have sent to their peace to
gain our peace,
Than to lie on a bed, torturing of the mind
In a
restless frenzy.

In this,
Macbeth is saying that he would rather be dead than live in fear of someone like Banquo
who knows about the witches' prophecy. Banquo has good reason to suspect Macbeth.
Macbeth's only option is to have Banquo murdered as well. Only then will Macbeth feel
secure in the throne.