John Wesley on 2 Kings 22:8

The book - That original book of the law of the Lord, given or written by the hand of Moses, as it is expressed, 2Chron 34:14, which by God's command was put beside the ark, Deut 31:26, and probably taken from thence and hid, by the care of some godly priest, when some of the idolatrous kings of Judah persecuted the true religion, and defaced the temple, and (which the Jewish writers affirm) burnt all the copies of God's law which they could find. It was now found among the rubbish, or in some secret place.