Deuteronomy 31:19, 21, 26
Deuteronomy 31:19 ESV
“Now therefore write this song and teach it to the people of Israel. Put it in their mouths, that this song may be a witness for me against the people of Israel.
Deuteronomy 31:26 ESV
“Take this Book of the Law and put it by the side of the ark of the covenant of the LORD your God, that it may be there for a witness against you.