Our parasha refers to mysterious battles and miracles, without going into much detail. The Torah does something else mysterious in that context. In one place, it says, "On this, it says in the Book of the Wars of Hashem, …" (Bamidbar 21:14). Later, it says, "On this the moshlim (authors or poets or ?) said, ‘Come to Cheshbon …’" (ibid.:27). What are these references that the Torah mentions? What work(s) is the Torah quoting?

Before presenting two classical approaches, we should note that this phenomenon of referring to apparently external sources arises in a few places in Tanach. In Yehoshua (10:13) and Shmuel (II, 1:18), the navi refers to things that are found in "Sefer Hayashar (The Book of the Straight)." In Yeshaya (34:16), the navi tells us to "search in the Book of Hashem." What are all of these works that our Holy Scriptures refer to?

Rashi in our parasha says that the Book of the Wars is not a book, but a reference to what people will say orally when discussing the miracles. The moshlim did not write anything. Rather, the Torah is talking about the prophecy of Bilam. In Yehoshua and Shmuel, he explains that Sefer Hayashar is actually our own Sefer Bereishit. So too, Yeshaya’s "Book of Hashem" is actually Sefer Bereishit, according to Rashi.

However, not all commentators take that approach. The Ramban (Bamidbar 21:13) explains in no uncertain terms what the Book of the Wars of Hashem is. "There were, in those generation, knowledgeable and wise men who would write a book about the big wars, as it was in all generations. The authors of these books were called moshlim because of their use of parables …" The Ibn Ezra and others take a similar approach.

It appears that Rashi, although being forced to find creative ways to explain each specific reference, has an understandable thesis. The Torah does not quote or paraphrase any external source. It only cross-references within Tanach (and even that, it usually does in a veiled manner). Rashi apparently reasoned that the Torah would not give credence to any other work, a work written by man, as bright and eloquent as he might be, by quoting it.

The Ramban and his camp apparently took a different approach. The Torah is full of quotes of less than holy people, from the King of S’dom to Paroh, to name a couple. It need not be the source of the statement that provides the holiness to the words found in the Torah. Rather, when Hashem decided to incorporate some previously external idea of wisdom, background, or general information within Tanach, its inclusion granted it a special status of words of Torah. There need not be a fear that such a reference gives parallel status or a carte blanche suggestion to delve into some external, humanly authored book, the way we delve into the Holy Scriptures themselves. Only that which is quoted, within its context in Tanach, is sacred.