I can roughly divide the text of the Torah into two categories - historical facts and prophecies. But, traditionally, they were all dictated by G-d to Moses.
The books of prophets retain a similar structure - it's a blend of history and prophecy.
While regarding the Torah, the Gemmorah says that every word has the same sacredness, what about the books of Prophets, that were not dictated by G-d literally, and were put in writing many generations later? Are the historical passages in them on the level of sacredness as the texts of G-d's prophecies?
Do any sources deal with this question?