What is "Cherev la'Shem"?
Rashi: Hashem brings [death via the sword] to the world.
Radak: The sword is of Hashem.
Why does it say "Ad Anah Lo Sishkoti"?
Radak: One moans over the Pelishtim, and asks the sword, how long will you not be quiet? Malbim - he says so, for the sword came against them twice.
What is "Tarech"?
Radak: It is your sheath (case). Malbim - this is a metaphor; the destroyer should return to his land, and not bombard kingdoms.
What is the meaning of "Herag'i"?
Rashi: It is an expression of calmness. Radak - it is similar to being quiet, like Demamah.
Malbim: Even if you will remain outside of your sheath, calm down a little and be quiet; do not kill constantly.