Numbers 21 · a question people ask
What is "The Book of the Wars of the LORD"?
Numbers quotes a few words from it about "the valleys of the Arnon" (21:14-15), and this is the only place the Bible names it. It isn't one of the books of the Bible, and the Bible says nothing more about it. The Bible quotes other books this way too: "Isn’t this written in the book of Jashar?" (Joshua 10:13; also 2 Samuel 1:18).
The verses
“Therefore it is said in The Book of the Wars of the LORD, “Vaheb in Suphah, the valleys of the Arnon, the slope of the valleys that incline toward the dwelling of Ar, leans on the border of Moab.””
“The sun stood still, and the moon stayed, until the nation had avenged themselves of their enemies. Isn’t this written in the book of Jashar? The sun stayed in the middle of the sky, and didn’t hurry to go down about a whole day.”
“(and he commanded them to teach the children of Judah the song of the bow; behold, it is written in the book of Jashar):”