Deuteronomy 17:19
And it shall be with him, and he shall read therein all the days of his life: that he may learn to fear the Lord his God, to keep all the words of this law and these statutes, to do them:
Cross-reference
In Deuteronomy 6:6-9, the same command to keep God's words in your heart and teach them parallels the king's daily reading.
Deuteronomy 11:18 urges laying up God's words in heart and soul, mirroring the king's lifelong meditation on the law.
Joshua 1:8 commands meditation on the law day and night for success, directly paralleling the king's constant reading.
Psalm 1:2 describes delighting in and meditating on the law day and night — the same practice required of the king.
Psalm 119:97-100 speaks of loving God's law and meditating all day, giving wisdom — exactly the king's goal in reading.
2 Timothy 3:15-17 affirms Scripture makes wise for salvation and equips for good works — fulfilling the king's purpose in reading.
In 2 Chronicles 34:18, Shaphan reads the rediscovered law to King Josiah — directly obeying the command for the king to hear it.
In 2 Chronicles 34:14, the rediscovery of the law book sets the stage for Josiah to fulfill the command for a king to read it.
John 5:39 calls for searching the Scriptures, which testify of Christ — a NT extension of the king's lifelong study.
In 1 Timothy 4:13, Paul urges Timothy to attend to public reading of Scripture — continuing the principle for spiritual leaders.