1)
Why does it say "va'Ya'avor v'Hinei Einenu"?
1.
Radak: I saw the tyrant, and a short time later, I turned [to him], and he was not!
2.
Malbim: He is not in this world
2)
What does "va'Avakshehu v'Lo Nimtza" add?
1.
Radak: Even his place was not found, for he and his seed were eradicated so thoroughly.
2.
Malbim: I looked if he is in the other world, for there are found people who pass from this world. He was not found there; his Nefesh is lost from the world to come.
