Words of Mormon 1:1 - 1:5

Words of Mormon 1:1 And now I, Mormon, being about to deliver up the record which I have been making into the hands of my son Moroni, behold I have witnessed almost all the destruction of my people, the Nephites.

A prophet name Mormon is now the commentator in this record. He tells us that he just about ready to give the records of the Nephites to his son Moroni. He has seen first hand the almost complete destruction of the Nephites.

Words of Mormon 1:2 And it is many hundred years after the coming of Christ that I deliver these records into the hands of my son; and it supposeth me that he will witness the entire destruction of my people. But may God grant that he may survive them, that he may write somewhat concerning them, and somewhat concerning Christ, that perhaps some day it may profit them.

Mormon tells us that he is writing many hundreds of years after the coming of Christ to the Nephites. His son Moroni will undoubtedly see the last of the Nephite civilization destroyed. But Mormon is praying that Moroni will live long enough to write the tale of the destruction and add some additional insights on the mission of Christ that they may be of benefit to future generations.

Words of Mormon 1:3 And now, I speak somewhat concerning that which I have written; for after I had made an abridgment from the plates of Nephi, down to the reign of this king Benjamin, of whom Amaleki spake, I searched among the records which had been delivered into my hands, and I found these plates, which contained this small account of the prophets, from Jacob down to the reign of this king Benjamin, and also many of the words of Nephi.

Mormon had been condensing down from many records a history of the Nephites and had gotten down to one King Benjamin. In looking for material to go back even further, Mormon found the plates that we have been reading from up to his point. The newly discovered plates included the words of Jacob down to Amaleki and the writings of Nephi.
[It sounds like Mormon was abridging from his time backwards. It also sounds like Mormon did not know about the plates of Nephi when he started this project. There must have been a lot of plates considering the numbers of years of history that the Nephites were a people on the promise land. It must have been hard to know all that was in the depository of records. Probably did not come with a catalog of the records.]

Words of Mormon 1:4 And the things which are upon these plates pleasing me, because of the prophecies of the coming of Christ; and my fathers knowing that many of them have been fulfilled; yea, and I also know that as many things as have been prophesied concerning us down to this day have been fulfilled, and as many as go beyond this day must surely come to pass—

Mormon has carefully gone over these newly discovered plates in the library and is impressed by the spirit to included them in his abridgement. They speak of Christ and His coming to the Nephites. Mormon wants to included all the prophecies concerning the Nephites and how they have been fulfilled thus far and what is to be fulfilled in their future.
[Wonder if there are things concerning the future of the Nephites in these plates of Nephi that Mormon did not know about?]

Words of Mormon 1:5 Wherefore, I chose these things, to finish my record upon them, which remainder of my record I shall take from the plates of Nephi; and I cannot write the hundredth part of the things of my people.

Mormon is nearly finished with his abridgement and will complete it out with the inclusion of these discovered plates of Nephi. The complete record can not even cover even a hundredth part of the history of the Nephites.