Who made it desolate?
Radak: Nebuchadnetzar. Even though he is not mentioned, it mentioned many shepherds, and he was at the head.
Verse 10 said that they made it a desolate Midbar. Why is this repeated?
Malbim: They made it so desolate that the Midbar designated this this part to be the most desolate in it - "v'Nashamu b'Soch Artzos Neshamos" (Yechezkel 30:7).
What is the meaning of "Avlah Alai"?
Rashi: [She mourned] in front of Me.
Radak, Malbim: This is an adjective describing Yisrael. It mourned its destruction against Me, saying that I caused it.
Why does it say "Ki Ein Ish Sam Al Lev"?
Radak: Why it was destroyed? Because no one put to heart My words and rebukes via My Nevi'im. They did not put to their hearts and heed them.
Radak citing Targum Yonasan: No one puts fear of Me to heart.
Malbim: [Yisrael say that I caused it. They did, for] they did not put to their hearts to repent!
