Joshua 15:8 - Matthew Poole's English Annotations on the Holy Bible

The border went up; properly, for the line went from Jordan and the Salt Sea, to the higher grounds nigh Jerusalem; and therefore the line is said to go down, Joshua 18:16, because there it takes a contrary course, and goes downwards to Jordan and the sea. Hinnom; a very pleasant place, but afterwards made infamous, 2 Kings 23:10. Of the Jebusite, i.e. of the city of the Jebusites, which was anciently called Jebusi, Joshua 18:28 Judges 19:10. The same is Jerusalem: it may seem hence, and from Deuteronomy 33:12 Joshua 18:28 Judges 1:21, that Jerusalem, properly, or at least principally, belonged to Benjamin; and yet it is ascribed to Judah also here, Joshua 15:63, and elsewhere, either because a part of the city was allotted to Judah; or because the Benjamites needed or desired the help and conjunction of this powerful tribe of Judah, for the getting and keeping of this most important place. And when the Benjamites had in vain attempted to drive out the Jebusites, this work was at last done by the tribe of Judah, who therefore had an interest in it by the right of war; as Ziklag, which belonged to the tribe of Simeon, being gotten from the Philistines by David, was adjoined by him to his tribe of Judah, 1 Samuel 27:6.