The central point of all scripture is to testify that Jesus Christ is the redeemer of the world (Words of Mormon). The Old Testament prophecies of His coming. The New Testament witnesses that He came. The Book of Mormon does both, because it starts before His birth and ends after Him coming to the Americas.
Many have debated, what does it mean to be the Redeemer? How does this happen. I do not know everything about the Atonement, which the act of redeeming the world from sin. There is the faith versus works debate. There is also the debate as to who will actually be saved. I do not know these answers. All I do know is that I need to continually work diligently to keep myself unspotted from the sins of the world. I will leave the judgment up to God.