This is one of my favorite scriptures:
“For behold, thus saith the Lord God: I will give unto the children of men line upon line, precept upon precept, here a little and there a little; and blessed are those who hearken unto my precepts, and lend an ear unto my counsel, for they shall learn wisdom; for unto him that receiveth I will give more; and from them that shall say, We have enough, from them shall be taken away even that which they have.” (2 Nephi 28:30)
This verse describes the manner in which I have learned the truthfulness of the Book of Mormon. It is through studying, praying, and practicing, my faith that I have received a witness that the Book of Mormon is true. What I mean is that, by doing these things, I have learned that the Book of Mormon fulfills its three purposes:
1. To show the great things that the Lord has done for our fathers;
2. To know the covenants of the Lord, and His promises to me;
3. To show that Jesus is the Christ.
I have found that the Book of Mormon fulfills all of these purposes.
1. Since I am a child of Abraham, my fathers are those who are in the Bible. The Book of Mormon has helped me to understand what God did for my fathers. It has prompted me to read more of the Bible, and to see what He has done for them. How He has delivered them. How He has cared for them. And the many things that He has done for them.
2. The Book of Mormon clarifies the covenants which the Lord has made, in the Bible. For example, I understand that Abrahamic covenant, which is that we children of Abraham will have the opportunity to be baptized in the Lord’s church. This promise was made to Abraham, Isaac, and Jacob, that their posterity would receive the ordinances of salvation. I understand this truth because of the Book of Mormon.
3. The Book of Mormon came because a fourteen year old young man prayed, and was visited by Heavenly Father and the Lord. Since they appeared to this young man, Joseph Smith, therefore I know that the Lord exists, and that He is the Christ.
I have learned all of these truths according the description in 2 Nephi 28:30.
This is what I wrote previously after reading 2 Nephi 28: Trying To Understand Rather Than Trying To Be Understood