Verse 9: And the border was drawn from the top of the hill unto (Josh. 18:15) the fountain of the water of Nephtoah, and went out to the cities of mount Ephron; and the border was drawn (1 Chron. 13:6) to Baalah, which is (Judg. 18:12) Kirjath-jearim…
[And it is bent, etc., וְתָאַ֙ר הַגְּב֜וּל וגו״] And the border shall be traced from the top of the mountain (Montanus). It circles, or goes around, etc. (Pagnine, Munster, all the Jews in Masius); it bends (Tigurinus); it extends (the Septuagint and Symmachus in Masius). And the border is traced, or is formed. Others: and the border draws a line, that is, it makes a line curved or oblique as in an arc. Or, with a line curved (or, oblique) the border extends, that is, directs itself (Vatablus). It defines that border from the apex of the mountain: Hebrew Syntax. There is a similar example in Psalm 10:2 (Piscator). The mountain defines that border, etc. (Junius and Tremellius). I think that תָּאַר is to trace out, to shape, to mark with lines drawn out; since it is certain that תּוֹאַר signifies the form and figure of a thing (Masius).
[Unto the villages of mount Ephron] Hebrew: unto the cities, etc. But what might that mount Ephron be, and what might its villages or cities be, you will not discover easily. There is an Ephron on the other side of Jordan, a fortified city, 1 Maccabees 5:46. There was another city of Ephron in Ephraim, 2 Chronicles 13:19. It is clear that this mount Ephron was distinct from those, and no mention of it is made in Joshua 18 (Bonfrerius). Arias Montanus understands the villages or cities that were adjacent to mount Ephron (Commentary on Joshua).
Of Mount Ephron, that is, belonging to or bordering upon Mount Ephron. Kirjath-jearim, called Kirjath-baal, Joshua 15:60; 18:14.
 Hebrew: וְתָאַ֙ר הַגְּב֜וּל מֵרֹ֣אשׁ הָהָ֗ר אֶל־מַעְיַן֙ מֵ֣י נֶפְתּ֔וֹחַ וְיָצָ֖א אֶל־עָרֵ֣י הַר־עֶפְר֑וֹן וְתָאַ֤ר הַגְּבוּל֙ בַּעֲלָ֔ה הִ֖יא קִרְיַ֥ת יְעָרִֽים׃
 Here, the verb is taken as impersonal; a subject needs to be supplied
 Psalm 10:2: “In the pride of the wicked he doth persecute (בְּגַאֲוַ֣ת רָ֭שָׁע יִדְלַ֣ק; a subject needs to be supplied) the poor: let them be taken in the devices that they have imagined.”
 See Genesis 29:17, for example: “Leah was tender eyed; but Rachel was beautiful and well favoured (יְפַת־תֹּ֖אַר וִיפַ֥ת מַרְאֶֽה׃, beautiful of form and beautiful of face).”
 Hebrew: אֶל־עָרֵי.
 1 Maccabees 5:45, 46: “Then Judas gathered together all the Israelites that were in the country of Galaad, from the least unto the greatest, even their wives, and their children, and their stuff, a very great host, to the end they might come into the land of Judea. Now when they came unto Ephron, (this was a great city in the way as they should go, very well fortified) they could not turn from it, either on the right hand or the left, but must needs pass through the midst of it.”
 2 Chronicles 13:19: “And Abijah pursued after Jeroboam, and took cities from him, Bethel with the towns thereof, and Jeshanah with the towns thereof, and Ephrain (עֶפְרוֹן/Ephron [kethib], עֶפְרַיִן/Ephrain [qere]) with the towns thereof.”