In Mormon 5:9, Mormon comments: "Therefore I write a small abridgment, daring not to give a full account of the things which I have seen, because of the commandment which I have received . . ." According to John Tvedtnes, although Mormon's abridgment comprises some sixty-four percent of the Book of Mormon (Mosiah through Mormon 7), Mormon uses the word "abridgment" only twice within the record (Words of Mormon 1:3; Mormon 5:9), with a third mention of his "abridgment of the record of the people of Nephi" occurring in the title page. Yet Mormon was not the first Nephite to have abridged records. In the beginning, Nephi had "abridged the record of [his] father" (1 Nephi 1:17). But neither Mormon nor Nephi invented the concept of abridging records. It was already a common phenomenon evidenced in the Bible.
Specific phrases and anachronisms, as well as reference to earlier writings containing greater detail, provide evidence for the abridgment of earlier records to produce our current Bible. For example, the phrase "unto this day" refers to an historical event marking the establishment of something that remained in place at the time of the individual who made the final record. We find the expression in works attributed to Moses and to Joshua, as well as various historical books (Judges through 2 Chronicles). The book of Judges, for example, covers such a long period of time that it must have been compiled from earlier records or oral traditions. That it was composed by a single historian is suggested by the fact that the book, as a whole, describes what the author saw as a cycle of sin, followed by captivity, then the cry of the people for assistance, and their delivery by a judge called by God. The perspective is clearly ex post facto rather than contemporary. [John A. Tvedtnes, "I Make This Small Abridgment," in The Most Correct Book, pp. 1-3]