Mormon says the following about the plates: “I made this record out of the plates of Nephi, and hid up in the hill Cumorah all the records which had been entrusted to me by the hand of the Lord, save it were these few plates which I gave unto my son Moroni.” (Mormon 6:6) Upon receiving them, Moroni adds: “Behold, my father hath made this record, and he hath written the intent thereof. And behold, I  would write it also if I had room upon the plates, but I have not; and ore have I none, for I am alone.” (Mormon 8:5)

But in spite of the lack of resources, Moroni somehow manages to abridge the record of Ether (15 chapters worth): “AND now I, Moroni, proceed to give an account of those ancient inhabitants who were destroyed by the hand of the Lord upon the face of this north country.” (Ether 1:1) He then records his own account (10 chapters worth): “NOW I, Moroni, after having made an end of abridging the account of the people of Jared, I had supposed not to have written more, but I have not as yet perished… Wherefore, I write a few more things, contrary to that which I had supposed… (Moroni 1:1,4) 

Where did he find the room to engrave 25 chapters worth of material? Did he make new plates?

Nephi contradicts himself in consecutive verses: “And I did teach my people to build buildings, and to work in all manner of wood, and of iron, and of copper, and of brass, and of steel, and of gold, and of silver, and of precious ores, which were in great abundance… And I, Nephi, did build a temple; and I did construct it after the manner of the temple of Solomon save it were not built of so many precious things; for they were not to be found upon the land…” (2 Nephi 5:15-16)

Nephi quotes Malachi’s yet unwritten words when he declares: "…the day soon cometh that all the proud and they who do wickedly shall be as stubble; and the day cometh that they must be burned." (1 Nephi 22:15; compare to Malachi 4:1) While typical of other anachronistic borrowings from the Bible, it sets up something more noteworthy. When Jesus appears to the Nephites, he tells them, “... Behold other scriptures I would that ye should write, that ye have not.” (3 Nephi 23:6) Among these unrecorded scriptures are the words of the Old Testament prophet, Malachi. Jesus then provides them with the text, which includes the line that Nephi had already recorded: “…and all that do wickedly, shall be stubble; and the day that cometh shall burn them up…” (3 Nephi 25:1) Did Jesus not know that Nephi had recorded this passage?