Rashi: That border will be the lottery of the remnant of Bnei Yehudah. Here, Chavel is an expression of a lottery, and so Yonason translates. Radak - i.e. it will be Hashem's portion. Above (5-6), he translated Chavel as Sefar (border).

Radak: This Chavel will still be for the remnant of Yehudah that will return from Galus Bavel.

Malbim: Eretz Pelishtim was part of the land that fell via lottery to Bnei Yisrael when the conquered the land in the days of Yehoshua. Now it will be to Yisrael again.

Radak #1: This verse and verse 6 apply to those places. When Yehudah will return from Galus Bavel, Eretz Pelishtim will be pasture for their flocks. Yir'un means Yir'u Tzonam.

Radak #2: Verse 6 applies to the Churban of Eretz Pelishtim. Shepherds will dwell there with their flocks due to destruction of the land. No people will dwell there. It will only be for pasture of flocks. Our verse discusses when Bnei Yehudah will return to Eretz Pelishtim. They will build houses for their needs.

Malbim: They will graze their flocks there.

Radak #1, Malbim: They will make the flock lie down at night in the destroyed houses of Ashkelon.

Radak #2: Yir'un and Yirbatzun are a Mashal, for they are compared to Tzon. Targum Yonasan is like this; he translates Yirbatzun as spending the night.