According to John Tvedtnes, one of the evidences for Mormon's reliance on extant annals is found in the story of the three Nephite disciples who had been promised by Christ that they would not die. In order to illustrate the effects of this translation, Mormon wrote:
And they were cast into prison by them who did not belong to the church. And the prisons could not hold them, for they were rent in twain. And they were cast down into the earth; but they did smite the earth with the word of God, insomuch that by his power they were delivered out of the depths of the earth; and therefore they could not dig pits sufficient to hold them. And thrice they were cast into a furnace and received no harm. And twice they were cast into a den of wild beasts; and behold they did play with the beasts as a child with a suckling lamb, and received no harm. (3 Nephi 28:19-22)
In 4 Nephi, recounting the success of the Church, Mormon writes of the beginning of apostasy, then of "another church which . . . did persecute the true church of Christ" (4 Nephi 1:23-29). Then follows a description of that false church's acts toward the three Nephites, which events are said to have occurred between 210 and 230 years after the birth of Christ (4 Nephi 1:27, 35). This description is very similar to that recorded in 3 Nephi 28. The question then follows: Were these two separate instances of persecution against the three Nephites?
According to Tvedtnes, it would appear that the recitation of the trials of the three disciples found in 3 Nephi 28 was included merely to illustrate the benefits of their translation. Why, then, did Mormon list them here and repeat them in 4 Nephi? The answer is found in 3 Nephi 28:24, where we read that Mormon intended to stop writing for a time. Indeed, the two chapters that immediately follow this statement comprise exhortations that appear to be closing remarks addressed to a later generation.
When, at length, Mormon returned to the abridgment and wrote 4 Nephi, he cut the story short. Centuries became but a few lines of text. But this time, at least, he included the story of the afflictions of the three disciples in its proper historical context.
It is the historian's perspective and access to written records that made it possible for Mormon to refer to the same event in two different parts of his work. These same factors made it possible for him to provide a measure of consistency to the text of his abridgement. [John A. Tvedtnes, "Mormon As an Abridger of Ancient Records," in The Most Correct Book, pp. 16-17]