2 Kings 23:20-24

And he slaughtered all the priests of the high places who were there on the altars, and burned human bones on them; then he returned to Jerusalem. Passover Reinstituted

Then the king commanded all the people, saying, “Celebrate the Passover to the Lord your God as it is written in this Book of the Covenant.”

Truly such a Passover had not been celebrated since the days of the judges who judged Israel, nor in all the days of the kings of Israel and the kings of Judah.

But in the eighteenth year of King Josiah, this Passover was celebrated to the Lord in Jerusalem.

Moreover, Josiah removed the mediums, the spiritists, the household idols, the idols, and all the abominations that were seen in the land of Judah and in Jerusalem, so that he might fulfill the words of the Law which were written in the book that Hilkiah the priest found in the house of the Lord.