Some versions have "the prophecy of Azariah the son of Oded," which is perhaps the true reading.

Renewed the altar - Dedicated it afresh, or perhaps enlarged it, that more sacrifices might be offered on it than ever before; for it cannot be supposed that this altar had no victims offered on it till the fifteenth year of the reign of Asa, who had previously been so zealous in restoring the Divine worship.

And when Asa heard these words, and the prophecy of Oded the prophet,.... Some think that besides the above words of Azariah the son of Oded, a prophecy of Oded his father was related by him, though not recorded; but rather Oded here is the same with the son of Oded; and so the Vulgate Latin and Syriac versions read Azariah the son of Oded; and so does the Alexandrian copy of the Septuagint version:

he took courage, and put away the abominable idols out of all the land of Judah and Benjamin; which were abominable to God, and all good men; besides the images and statues he had broken before, he removed other idols that remained, being animated and emboldened by the speech of the prophet:

and out of the cities which he had taken from Mount Ephraim: the same which his father Abijah had taken from Jeroboam, 2 Chronicles 13:19 and which perhaps, upon the approach of the Ethiopians, revolted from Asa, or were restored by them to Jeroboam, and Which Asa retook upon his conquest of them:

and renewed the altar of the Lord before the porch of the Lord; the altar of burnt offering, which had never been repaired since it was made by Solomon; perhaps he anew overlaid it with brass that being worn out, or become very thin in some places.

Completion of the reform in worship, and the renewal of the covenant. - 2 Chronicles 15:8. The speech and prophecy of the prophet strengthened the king to carry out the work he had begun, viz., the extirpation of idolatry from the whole land. In 2 Chronicles 15:8 the words הנּניא עדד are surprising, not only because the prophet is called in 2 Chronicles 15:1, not Oded, but Azariah the son of Oded, but also on account of the preceding הנּבוּאה in the absolute state, which cannot stand, without more ado, for the stat. constr. נבוּאת (cf. 2 Chronicles 9:29). The view of Cler. and Ew., that by an orthographical error בּן עזריהוּ has been dropped out, does not remove the difficulty, for it leaves the stat. absol. הנּבוּאה .lo unexplained. This is also the case with the attempt to explain the name Oded in 2 Chronicles 15:8 by transposing the words Azariah ben Oded, 2 Chronicles 15:1, so as to obtain Oded ben Azariah (Movers); and there seems to be no other solution of the difficulty than to strike out the words Oded the prophet from the text as a gloss which has crept into it (Berth.), or to suppose that there is a considerable hiatus in the text caused by the dropping out of the words בּן עזריהוּ דּבּר אשׁר.

(Note: C. P. Caspari, der Syrisch-ephraimitische Krieg, Christian. 1849, S. 51, explains the absol. הנּבוּאה by an ellipse, as in Isaiah 3:14; Isaiah 8:11, "the prophecy (that) of Oded," but answers the question why Oded is used in 2 Chronicles 15:8 instead of Azarjahu ben Oded by various conjectures, none of which can be looked upon as probable.)

התחזק corresponds to חזקוּ. Asa complied with the exhortation, and removed (ויּעבר, as in 1 Kings 15:12) all abominations (idols) from the whole land, and from the cities which he had taken from Mount Ephraim: these are the cities which Asa's father Abijah had conquered, 2 Chronicles 13:19. "And he renewed the altar before the porch," i.e., the altar of burnt-offering, which might stand in need of repairs sixty years after the building of the temple. The Vulg. is incorrect in translating dedicavit, and Berth. in supposing that the renovation refers only to a purification of it from defilement by idolatry. חדּשׁ is everywhere to renew, repair, restaurare; cf. 2 Chronicles 24:4. - But in order to give internal stability to the reform he had begun, Asa prepared a great sacrificial festival, to which he invited the people out of all the kingdom, and induced them to renew the covenant with the Lord. 2 Chronicles 15:9. He gathered together the whole of Judah and Benjamin, and the strangers out of Ephraim, Manasseh, and Simeon, who dwelt among them. Strangers, i.e., Israelites from the ten tribes, had come over as early as Rehoboam's reign to the kingdom of Judah (2 Chronicles 11:16); these immigrations increased under Asa when it was seen that Jahve was with him, and had given him a great victory over the Cushites. It is surprising that Simeon should be mentioned among the tribes from which Israelites went over to the kingdom of Judah, since Simeon had received his heritage in the southern district of the tribal domain of Judah, so that at the division of the kingdom it would not well separate itself from Judah, and join with the tribes who had revolted from the house of David. The grouping together of Simeon, Ephraim, and Manasseh, both in our verse and in 2 Chronicles 34:6, can consequently scarcely be otherwise explained than by the supposition, either from the cities assigned to them under Joshua into districts in the northern kingdom (Berth.), or that the Simeonites, though politically united with Judah, yet in religious matters were not so, but abstained from taking part in the Jahve-worship in Jerusalem, and had set up in Beersheba a worship of their own similar to that in Bethel and Dan. In such a case, the more earnest and thoughtful people from Simeon, as well as from Ephraim and Manasseh, may have gone to Jerusalem to the sacrificial festival prepared by Asa. In favour of this last supposition we may adduce the fact that the prophet Amos, Amos 5:5; Amos 4:4; Amos 8:14, mentions Beersheba, along with Bethel and Gilgal, as a place to which pilgrimages were made by the idolatrous Israelites.

And when Asa heard these words, and the prophecy of Oded the prophet, he took courage, and put away the abominable idols out of all the land of Judah and Benjamin, and out of the cities which he had taken from mount Ephraim, and renewed the altar of the LORD, that was before the porch of the LORD.

15:8 Of Oded - Of Azariah, ver.1, who was also called by his father's name Oded.

abominable...: Heb. abominations

Margin when Asa

Chapter 14 describes the outward prosperity of the kingdom, and Asa's superficial reformation; chapter 15 the true reformation.

8. when Asa heard . the prophecy of Oded the prophet-The insertion of these words, "of Oded the prophet," is generally regarded as a corruption of the text. "The sole remedy is to erase them. They are, probably, the remains of a note, which crept in from the margin into the text" [Bertheau].

he took courage-Animated by the seasonable and pious address of Azariah, Asa became a more zealous reformer than ever, employing all his royal authority and influence to extirpate every vestige of idolatry from the land.

and out of the cities which he had taken from mount Ephraim-He may have acquired cities of Ephraim, the conquest of which is not recorded (2Ch 17:2); but it has been commonly supposed that the reference is to cities which his father Abijah had taken in that quarter (2Ch 13:19).

renewed the altar of the Lord . before the porch-that is, the altar of burnt offering. As this was done on or about the fifteenth year of the reign of this pious king, the renewal must have consisted in some splendid repairs or embellishments, which made it look like a new dedication, or in a reconstruction of a temporary altar, like that of Solomon (2Ch 7:7), for extraordinary sacrifices to be offered on an approaching occasion.

15:1-19 The people make a solemn covenant with God. - The work of complete reformation appeared so difficult, that Asa had not courage to attempt it, till assured of Divine assistance and acceptance. He and his people offered sacrifices to God; thanksgiving for the favours they had received, and supplication for further favours. Prayers and praises are now our spiritual sacrifices. The people, of their own will, covenanted to seek the Lord, each for himself, with earnestness. What is religion but seeking God, inquiring after him, applying to him upon all occasions? We make nothing of our religion, if we do not make heart-work of it; God will have all the heart, or none. Our devotedness to God our Saviour, should be avowed and shown in the most solemn and public manner. What is done in hypocrisy is a mere drudgery.