What is the meaning of "v'Nasav ha'Gevul mi'Ba'alah Yamah"?
Rashi: Now [after enveloping the strip from Binyamin,] the border returned to go westward.
Malbim: Yam is a sea (or a place called Yam) southeast of Ba'alah. The border [from west to east 1 ] jutted out to the north to include Ba'alah, and afterwards turned at a right angle to the south, towards Yam.
Malbim: Below (18:15), the verse describes Binyamin's southern border from west to east, and says that after Ba'alah, the border jutted out to the south towards Yam. (However, the verses here describes Yehudah's northern border from east to west. Why does it switch regarding Ba'alah?!
Har Se'ir is Esav's inheritance! Why is it in Yehudah's portion?
Malbim: There is a mountain chain in Yehudah; its south end touches Har Se'ir. Part of the chain in Yehudah is called Har Se'ir. 1
Why is this name give to part of the chain near Yehudah's northern border, far from [Esav's] Har Se'ir in the south? (PF)
Below (19:22,34) we find that Beis Shemesh is in the portion of Yisachar and Naftoli!