2 Kings 23:20-24

He slew all the priests of the high places that were there upon the altars and burned men's bones upon them [to defile the places forever]. Then he returned to Jerusalem.

The king commanded all the people, Keep the Passover to the Lord your God, as it is written in this Book of the Covenant.

Surely such a Passover was not held from the days of Israel's judges, even in all the days of the kings of Israel or Judah.

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

Moreover, Josiah put away the mediums, the wizards, the teraphim (household gods), the idols, and all the abominations that were seen in Judah and in Jerusalem, that he might establish the words of the law written in the book found by Hilkiah the priest in the house of the Lord.