Chapter 34 of 2 Chronicles in the King James Version of the Bible tells the story of King Josiah's reign and his efforts to restore the worship of God in Judah. At the age of eight, Josiah became king and reigned for thirty-one years. He did what was right in the sight of the Lord, following the example of his ancestor David.
In the eighth year of his reign, when he was still a young man, Josiah began to seek God and purge Judah and Jerusalem of idolatry. He ordered the repair and cleansing of the temple of the Lord, and during this process, a book of the Law was found. The book was brought to Josiah, and upon hearing its words, he tore his clothes in distress because he realized that the nation had not been following God's commands.
Josiah summoned the prophetess Huldah, who confirmed that God would bring disaster upon Judah because they had forsaken Him. However, because Josiah had humbled himself before God, the disaster would not come during his lifetime.
The king gathered the people and read the Law to them, renewing the covenant between God and the nation. He then proceeded to remove all the idols and altars of foreign gods from the land. Josiah celebrated a Passover festival, which had not been observed in such a manner since the days of the judges.