Deuteronomy 31:23-26

King James Version

²³ And he gave Joshua the son of Nun a charge, and said, Be strong and of a good courage: for thou shalt bring the children of Israel into the land which I sware unto them: and I will be with thee.

²⁴ And it came to pass, when Moses had made an end of writing the words of this law in a book, until they were finished,

²⁵ That Moses commanded the Levites, which bare the ark of the covenant of the Lord, saying,

²⁶ Take this book of the law, and put it in the side of the ark of the covenant of the Lord your God, that it may be there for a witness against thee.