Holy of Holies: Contained: A Written Copy of the Divine Law
Source: TTT
Deuteronomy 31:26
“Take this Book of the Law and place it beside the ark of the covenant of the LORD your God, so that it may remain there as a witness against you.
2 Kings 22:8
Then Hilkiah the high priest said to Shaphan the scribe, “I have found the Book of the Law in the house of the LORD!” And he gave it to Shaphan, who read it.