From there the border crossed over to the southern slope of Luz (that is, Bethel) and went down to Ataroth-addar on the hill south of Lower Beth-horon.
We have here the lot of the tribe of Benjamin, which Providence cast next to Joseph on the one hand, because Benjamin was own and only brother to Joseph, and was little Benjamin (Psa 68:27), that needed the protection of great Joseph, and yet had a better protector, for the Lord shall cover him all the day long, Deu 33:12.
Commenting on Joshua 18:11-28
And the border went over from thence towards Luz,.... From Bethaven, where the northern border ended, the western began, and went on to Luz: to the side of Luz, which is Bethel, southward; that is, passed along, leaving that city to the south, which formerly was called Luz, but now Bethel, which though distinct places formerly, yet being very near, might in process of time...
And the border went over from thence toward Luz, to the side of Luz, which [is] Bethel, southward; and the border descended to Atarothadar, near the hill that [lieth] on the south side of the nether Bethhoron. (k) Which was in the tribe of Ephraim: another Bethel was in the tribe of Benjamin.