Moroni was "commanded" by his father to "finish" his father's abridgment of the large plates of Nephi concerning "the sad tale of the destruction of [his] people" and then "hide up the records in the earth" (Mormon 8:1-4). According to Donl Peterson, Moroni apparently first met this responsibility with an epilogue that now comprises thirteen verses (Mormon 8:1-13). He ended those verses with the following: "Behold, I make an end of speaking concerning this people. I am the son of Mormon, and my father was a descendant of Nephi" (Mormon 8:12-13).
After adding this brief epilogue, and before hiding the plates, Moroni then apparently wrote the heading and first paragraph of the title page, which reads as follows:
The Book of Mormon
An account written by the hand of Mormon, upon plates taken from the plates of Nephi.
Wherefore, it is an abridgment of the record of the people of Nephi, and also of the Lamanites--Written to the Lamanites which are a remnant of the house of Israel, and also to Jew and Gentile--Written by way of commandment, and also by the spirit of prophecy and of revelation--Written and sealed up and hid up unto the Lord, that they might not be destroyed, to come forth by the gift and power of God, unto the interpretation thereof--Sealed by the hand of Moroni, and hid up unto the Lord, to come forth in due time by way of the Gentile--the interpretation thereof by the gift of God.
According to Peterson, whatever else Moroni had in mind at that time, aside from survival itself, we are not told. [H. Donl Peterson, Moroni: Ancient Prophet Modern Messenger, pp. 18-19] [For the proposed chronological completion of the Title Page, see the commentary on Moroni 1:1]