'Eighteenth' in the Bible

In the eighteenth year of Israel’s King Jeroboam, Abijah became king over Judah

In the eighteenth year of his reign, in order to cleanse the land and the temple, Josiah sent Shaphan son of Azaliah, along with Maaseiah the governor of the city and the court historian Joah son of Joahaz, to repair the temple of the Lord his God.

In the eighteenth year of Josiah’s reign, this Passover was observed.