How is his mouth like a sharp sword?
Rashi: To rebuke Resha'im and prophesized punishments for them.
Radak: I cannot refrain from prophesizing, for He made my mouth a sharp sword to tell future events, without fear. This refers to prophecies for Yisrael, who are close to him; a sword strikes only someone near. Malbim - I gave sharp rebukes to Yisrael. One holds a sword in his hand.
Why did He hide Yeshayah?
Rashi: So they cannot harm him. Radak - Yisraelim will not be able to harm me, even though I spoke evils about them.
Malbim: One holds a sword in his hand. It can be hidden, so one sees only the hand. I prophesized in the name of Hashem; people did not seek to harm me, for they realized that the words are Hashem's.
What is "Barur"?
Rashi: It is shining.
Radak: It is cleaned until it is clear. An arrow shoots to far away; this corresponds to prophecies for nations far away (Malbim - and in the distant future).
What is "Ashpaso"?
Rashi: His quiver to hold arrows.
Why did he say that Hashem hid him in His quiver?
Radak: He compared himself to an arrow; they are hidden in a quiver.
Malbim: People did not realize that I am prepared to shoot.
