This made me think about how much easier it is to believe when we receive our own witness, than it is to believe in someone else's witness. Having not been the one to receive the vision, Sariah had to have faith that her husband was being led of God. This reminded me of a scripture from the Doctrine and Covenants that speaks about gifts of the spirit: "To some it is given by the Holy Ghost to know that Jesus Christ is the Son of God, and that he was crucified for the sins of the world. To others it is given to believe on their words, that they also might have eternal life if they continue faithful." D.&C. 46:13,14
The rest of this chapter talks about the records that Nephi and his brothers were able to obtain. It explains what was contained in the records. Not only did it contain the spiritual writings that would help them to stay close to God, but it also contained a geneology of their forefathers. But most importantly, it contained the word of God, and the commandments. This would enable them to preserve the commandments for their children, and as we later read about, an entire nation.