15 Moreover the altar that was at Bethel, and the high place which Jeroboam the son of Nebat, who made Israel sin, had made, both that altar and the high place he broke down; and he burned the high place and crushed it to powder, and burned the wooden image. 16 As Josiah turned, he saw the tombs that were there on the mountain. And he sent and took the bones out of the tombs and burned them on the altar, and defiled it according to the word of the Lord which the man of God proclaimed, who proclaimed these words. 17 Then he said, "What gravestone is this that I see?" So the men of the city told him, "It is the tomb of the man of God who came from Judah and proclaimed these things which you have done against the altar of Bethel." 18 And he said, "Let him alone; let no one move his bones." So they let his bones alone, with the bones of the prophet who came from Samaria. 19 Now Josiah also took away all the shrines of the high places that were in the cities of Samaria, which the kings of Israel had made to provoke the Lord to anger; and he did to them according to all the deeds he had done in Bethel 20 He executed all the priests of the high places who were there, on the altars, and burned men's bones on them; and he returned to Jerusalem.
21 Then the king commanded all the people, saying, "Keep the Passover to the Lord your God, as it is written in this Book of the Covenant. 22 Such a Passover surely had never been held since the days of the judges who judged Israel, nor in all the days of the kings of Israel and the kings of Judah. 23 But in the eighteenth year of King Josiah this Passover was held before the Lord in Jerusalem.
24 Moreover Josiah put away those who consulted mediums and spiritists, the household gods and idols, all the abominations that were seen in the land of Judah and in Jerusalem, that he might perform the words of the law which were written in the book that Hilkiah the priest found in the house of the Lord.
Matthew Henry's Commentary on 2 Kings 23:15-24
Commentary on 2 Kings 23:15-24
(Read 2 Kings 23:15-24)
Josiah's zeal extended to the cities of Israel within his reach. He carefully preserved the sepulchre of that man of God, who came from Judah to foretell the throwing down of Jeroboam's altar. When they had cleared the country of the old leaven of idolatry, then they applied themselves to the keeping of the feast. There was not holden such a passover in any of the foregoing reigns. The revival of a long-neglected ordinance, filled them with holy joy; and God recompensed their zeal in destroying idolatry with uncommon tokens of his presence and favour. We have reason to think that during the remainder of Josiah's reign, religion flourished.