[these things should come unto their brethren]: The Book of Mormon. Moroni is telling us that it was through faith that his Nephite fathers obtained the promise that the gospel would be preached to “their brethren,” or the Lamanites. One of the great purposes of the Book of Mormon, and indeed Mormon’s parting thought, is directed to the Lamanites. This is a promise that was extracted from God through the faith of those requesting this divine favor.