1)
What sword is this?
1.
Radak: It is of Galus; may I not be finished off in Galus.
2.
Malbim: It is the hunters' swords (refer to 22:17:1:2).
2)
From what dog must he be saved?
1.
Megilah 15b: Initially Esther called Achashverosh a dog. She retracted, and called him a lion (verse 22).
2.
Radak: Dog, lion and Re'em (verse 22) are parables for Nochri kings that we are among them in Galus. Each is called according to his grandeur.
3)
What is "Yechidasi"?
1.
Radak: It is the Neshamah, which dwells alone in physical houses (the body).
2.
Malbim: It is the one matter that remains after they plundered all my property - my life!