The works of Moses make it clear that there was a Word among earlier people. Moses cites it and quotes something from it (Numbers 21:14-15, 27-30). The historical part of that Word was called the Wars of Jehovah, and its prophetical part was called the Pronouncements.
From the historical part of that Word, Moses quoted the following:
Therefore it says in the Book of the Wars of Jehovah: “I was going to Suphah and the brooks of the Arnon, and the channel of the rivers of water that sloped down where Ar is living and then appears by the border of Moab.” (Numbers 21:14-15)
The “wars of Jehovah” in that Word, like the wars in ours, meant and depicted the Lord’s battles with the hells and victory over them when he would come into the world. The same battles are meant and depicted in the historical portions of our Word–for example, Joshua’s wars with the nations in the land of Canaan and the wars waged by the judges and the kings of Israel.
The following is a quotation from the prophetic parts of that Word:
Therefore the Makers of Pronouncements say: “Walk to Heshbon. the city of Sihon will be built and reinforced. For a fire went out from Heshbon, a flame the city of Sihon; it consumed Ar of Moab, the possessors of the heights of the Arnon. Woe to you, Moab. You have perished, O people of Chemosh. He has given his sons as fugitives and his daughters into captivity to Sihon, king of the Amorites. We killed them with arrows. Heshbon has perished all the way to Dibon, and we devastated [it] all the way to Nophah, which [stretches] all the way to Medeba.” (Numbers 21:27-30)
Translators have rendered the name here as “the Maker of Proverbs,” but it ought to be “the Maker of Pronouncements” or “the Prophetic Pronouncements.” This is clear from the meaning of the word meshalim in Hebrew: it means not only proverbs but also prophetic pronouncements. For example, in Numbers 23:7, 18 and 24:3, 15 it says Balaam gave his pronouncements, which was in fact a prophecy about the Lord. His pronouncement is called a mashal, which is the singular. For another thing, the material that Moses quotes from the Word is in fact prophecies, not proverbs.
That Word was just as divinely inspired. This is clear from Jeremiah where we read almost identical words:
A fire went out from Heshbon and a flame from the midst of Sihon that consumed the corner of Moab and the top of children of tumult. Woe to you, Moab. The people of Chemosh have perished. For they have taken your sons into captivity and your daughters into captivity. (Jeremiah 48:45-46)
Both David and Joshua also mention a prophetic book of the ancient Word called the Book of Jasher (“Book of the Upright Person”). David refers to it thus:
David lamented over Saul and over Jonathan and wrote to teach the children of Judah the bow; look at what was written in the book of Jasher. (2 Samuel 1:17-18)
And Joshua refers to it thus;
Joshua said, “O sun, stand still in Gibeon. O moon, stand still in the valley of Aijalon. Is this not written in the Book of Jasher?” (Joshua 10:12)
from True Christianity, Section 265