1)
How will Hashem make you "Charbah" and "Cherpah"?
1.
Radak: Your land will be desolate, and you will be shamed to the nations around you. They will be astounded at you and whistle over you.
2.
Malbim: This begins to explain "v'Hishlachta Osam El Toch ha'Esh
2)
Why does it say "l'Einei Kol Over"?
1.
Radak: Also all who pass by will be astounded at you and whistle over you.