New Defender's Study Bible Notes
15:9 in abundance. Even though the ten tribes separated themselves from Judah and Jerusalem, and eventually went into Assyrian exile, never to return, this and other passages indicate that many of the most spiritually minded people among other tribes did return, to continue in the kingdom of the Davidic promises. No doubt all the tribes were thus represented in the Judaic heritage.
15:10 fifteenth year. Asa had had ten years of peace (II Chronicles 14:1), but then came the war with Zerah. Following five years of conflict and uncertainty, the land once again had peace for twenty more years (II Chronicles 15:19).
15:16 Maachah the mother of Asa. Maachah was presumably the “Queen Mother” of Judah. She had been Rehoboam’s wife and the mother of Abijah (II Chronicles 11:21; 13:2) and thus was actually Asa’s grandmother. Probably Asa’s real mother (not named in the narrative) had died when Asa was young, so that Maachah had acted as his mother and thus had been honored as queen mother until she began to worship idols, a situation which Asa finally could not allow to continue.
15:17 not taken away. According to II Chronicles 14:3,5, Asa did take away the high places out of Judah, but this verse indicates he had been unable to get them removed from the rest of Israel.