Yet will I bring an heir unto thee, O inhabitant of Mareshah. "Mareshah" sounds like Morashah, the Hebrew word for "inheritance;" so the play is, "I will bring an inheritor who shall claim your Heritage town."
The "heir" is the Assyrian king, Sargon, into whose possession the city shall pass. Mareshah (Joshua 15:44; 2 Chronicles 14:9) was near Achzib, one mile southcast of Beit Jibrin, and is now called Mer'ash.
He shall come, etc.; better, the glory of Israel shall come to Adullam; i.e. the nobility (comp. Isaiah 5:13) of Israel shall fly for refuge to such places as the cave of Adullam, David's asylum (1 Samuel 22:1, 1 Samuel 22:2).
So the Vulgate. The LXX. has, κληρονομία ἓως ὀδυλλὰμ ἥξει ἡ δόξα τῆς θυγατρὸς ἰσραήλ "The inheritance shall come to Odullam, even the glory of the daughter of Israel." But Rosenmuller, Henderson, Pusey, and others take the sentence as in the Authorized Version, making "the glory of Israel" in apposition with "Adullam," and understanding by "he" the heir or enemy.
One knows no reason why Aduliam should be honoured with the above-named title; so the rendering given above is preferable. There is probably a paronomasia intended, "The glory of the Lord shall set (ad olam) forever."
The city of Adullam, hod. Aid-el-Mah, lay in the valley of Elah, ten miles northwest of Hebron, halfway between Sochoh and Keilah. It was of great antiquity, being mentioned as the birthplace of Hirah, the friend of Judah (Genesis 38:12), and one of the cities fortified by Rehoboam (2 Chronicles 11:7).
In its neighbourhood is the celebrated cave, Mugha et Khureitun, which is pointed out as the traditional hold of David, and which has been carefully explored by Mr. Tyrwhitt Drake, of the Palestine Exploration Fund.