A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
4 Kings (2 Kings) 22:1
kg2 22:1JOSIAH'S GOOD REIGN. (Kg2 22:1-2)
Josiah was eight years old when he began to reign--Happier than his grandfather Manasseh, he seems to have fallen during his minority under the care of better guardians, who trained him in the principles and practice of piety; and so strongly had his young affections been enlisted on the side of true and undefiled religion, that he continued to adhere all his life, with undeviating perseverance, to the cause of God and righteousness.
4 Kings (2 Kings) 22:3
kg2 22:3HE PROVIDES FOR THE REPAIR OF THE TEMPLE. (Kg2 22:3-7)
in the eighteenth year of king Josiah--Previous to this period, he had commenced the work of national reformation. The preliminary steps had been already taken; not only the builders were employed, but money had been brought by all the people and received by the Levites at the door, and various other preparations had been made. But the course of this narrative turns on one interesting incident which happened in the eighteenth year of Josiah's reign, and hence that date is specified. In fact the whole land was thoroughly purified from every object and all traces of idolatry. The king now addressed himself to the repair and embellishment of the temple and gave directions to Hilkiah the high priest to take a general survey, in order to ascertain what was necessary to be done (see on Ch2 34:8-15).
4 Kings (2 Kings) 22:8
kg2 22:8HILKIAH FINDS THE BOOK OF THE LAW. (Kg2 22:8-15)
Hilkiah said . . . I have found the book of the law in the house of the Lord, &c.--that is, the law of Moses, the Pentateuch. It was the temple copy which, had been laid (Deu 31:25-26) beside the ark in the most holy place. During the ungodly reigns of Manasseh and Amon--or perhaps under Ahaz, when the temple itself had been profaned by idols, and the ark also (Ch2 35:3) removed from its site; it was somehow lost, and was now found again during the repair of the temple [KEIL]. Delivered by Hilkiah the discoverer to Shaphan the scribe [Kg2 22:8], it was by the latter shown and read to the king. It is thought, with great probability, that the passage read to the king, and by which the royal mind was so greatly excited, was a portion of Deuteronomy, the twenty-eighth, twenty-ninth, and thirtieth chapters, in which is recorded a renewal of the national covenant, and an enumeration of the terrible threats and curses denounced against all who violated the law, whether prince or people. The impressions of grief and terror which the reading produced on the mind of Josiah have seemed to many unaccountable. But, as it is certain from the extensive and familiar knowledge displayed by the prophets, that there were numbers of other copies in popular circulation, the king must have known its sacred contents in some degree. But he might have been a stranger to the passage read him, or the reading of it might, in the peculiar circumstances, have found a way to his heart in a manner that he never felt before. His strong faith in the divine word, and his painful consciousness that the woeful and long-continued apostasies of the nation had exposed them to the infliction of the judgments denounced, must have come with overwhelming force on the heart of so pious a prince.
4 Kings (2 Kings) 22:12
kg2 22:12the king commanded . . . Go, inquire of the Lord for me, &c.--The agitated feelings of the king prompted him to ask immediate counsel how to avert those curses under which his kingdom lay; and forthwith a deputation of his principal officers was sent to one endowed with the prophetic spirit.
Ahikam--a friend of Jeremiah (Jer 26:24).
4 Kings (2 Kings) 22:14
kg2 22:14Achbor--or Abdon (Ch2 34:20), a man of influence at court (Jer 26:22). The occasion was urgent, and therefore they were sent--not to Zephaniah (Zep 1:1), who was perhaps young--nor to Jeremiah, who was probably absent at his house in Anathoth, but to one who was at hand and known for her prophetic gifts--to Huldah, who was probably at this time a widow. Her husband Shallum was grandson of one Harhas, "keeper of the wardrobe." If this means the priestly wardrobe, [Harhas] must have been a Levite. But it probably refers to the royal wardrobe.
she dwelt . . . in the college--rather, "in the Misnah," taking the original word as a proper name, not a school or college, but a particular suburb of Jerusalem. She was held in such veneration that Jewish writers say she and Jehoiada the priest were the only persons not of the house of David (Ch2 24:15-16) who were ever buried in Jerusalem.
4 Kings (2 Kings) 22:15
kg2 22:15she said unto them, Thus saith the Lord God of Israel, Tell the man that sent you to me--On being consulted, she delivered an oracular response in which judgment was blended with mercy; for it announced the impending calamities that at no distant period were to overtake the city and its inhabitants. But at the same time the king was consoled with an assurance that this season of punishment and sorrow should not be during his lifetime, on account of the faith, penitence, and pious zeal for the divine glory and worship which, in his public capacity and with his royal influence, he had displayed.