Chapter 29 largely deals with the writing of other books of scripture other than the Bible. Nephi quotes the Lord as saying that the testimony of two nations shall run together and testify that God is the same yesterday, today, and forever.
I think that two testimonies of God’s work on the earth is significant. Many people believe that God is different and that as Nephi stated in the last chapter, God has left His work in the hands of men. This is not so. God is still very active in His work and glory (Moses 1:39). He wants us to know that he is the same, so he has commanded the prophets throughout the world to write and testify of him.
A Bible, A Bible!
I've always found it interesting how some Christian religions know the Bible is from God yet deny that the Book of Mormon comes from the same divine source. The logic and arguments for and against the Book of Mormon are numerous. But at the heart of every argument against the Book of Mormon is the question of authenticity. Many believe the Joseph Smith wrote it instead of translating it … many believe that the Book of Mormon doesn't come from God. But those same people believe that the Bible is inspired of God. They are stuck on the question of Joseph Smith being a prophet or not. Thankfully Moroni saw this dilemma and instructed everyone who reads the Book of Mormon to ask God if it is true or not. Those who have a sincere desire to know the truth will receive a personal witness of the truth of the Book of Mormon (Moroni 10:3-9).
Let me also address the question of authenticity in another way. At church this Sunday, the counselor in the Elder's quorum shared a missionary experience with us. He is a convert to the Church. He had gone on a few visits with the missionaries the previous week. One of the people they visited was this young man who questioned everything the missionaries taught him. He kept asking them, "how do you know for sure Joseph Smith is a true prophet? How do you know for sure the Book of Mormon is true?" He wanted solid proof that the Church is true. At this point, the counselor began addressing this young man. He said, "you believe in Jesus Christ, correct?" The young man replied, "yes." Then the counselor said told said, "I assume you've not seen Jesus Christ, but you know he lived and did what the Bible tells us he did. Is that correct?" The young man again said, "yes." Then the counselor said that believing the Book of Mormon and that Joseph Smith was a prophet of God is similar to believing Christ is real. You must gain that testimony for yourself through study and prayer.
I think that those who forcefully argue against the Book of Mormon (those who say there is no more word of God besides the Bible) love the Bible and think the Book of Mormon detracts from it. In reality, if these people were really searching the truth, they would prayerfully consider the Book of Mormon after reading it and studying its teachings.
“The argument is, as the Lord suggests, most foolish. It is our modern counterpart to those of Jesus' day who rejected him in the pretense of being loyal to the Law of Moses, the irony being that loyalty to the Law of Moses demanded acceptance of Jesus as the Christ. The purpose of the Law of Moses was to teach and testify of Christ. Such is also the purpose of the Book of Mormon, it being the most Christ-centered book ever written. Yet it is rejected in the name of loyalty to the Bible. The logical extension of such reasoning would be to reject the Gospel of Mark in the name of loyalty to Matthew or to reject the witness of Peter in the pretense of loyalty to Paul and his teachings.” (McConkie and Millet, Doctrinal Commentary on the Book of Mormon, vol. 1, p. 347)
Out of the Books Will We be Judged
A warning also comes with this doctrine. We will be judged according to that which is written in the books written by the prophets (v. 11). Since we have the Bible, the Book of Mormon, the Doctrine & Covenants and the Pearl of Great Price, we will be judged according to that which is written in those books. Also, we will be judged according to the word of the modern-day prophets. Their words are found in the Ensign and other Church materials.
Since I'm an IT person, I kind of view reading the scriptures and the latest General Conference material like anti-virus software. In order to protect your personal computer (or your soul) you should install a base version of some anti-virus software (read the scriptures). Then in order to guard against the most recent virus attacks (or Satan's temptations), you must subscribe to an anti-virus update service (or listen to and read the latest General Conference).
More Scripture to Come
We have been taught from the scriptures that more scriptures will be revealed. We've discussed earlier that some sealed scriptures will be revealed to the world. And now in 2 Nephi 29:13 we learn that not only will we have the Bible and Book of Mormon, but we will have the scriptures of the Lost Tribes of Israel.
“Lost books are among the treasures yet to come forth. Over twenty of these are mentioned in the existing scriptures. Perhaps most startling and voluminous will be the records of the lost tribes of Israel (see 2 Nephi 29:13). We would not even know of the impending third witness for Christ except through the precious Book of Mormon, the second witness for Christ! This third set of sacred records will thus complete a triad of truth. Then, just as the Perfect Shepherd has said, ‘My word also shall be gathered in one’ (v. 14). There will be ‘one fold and one shepherd’ (1 Nephi 22:25 in a welding together of all the Christian dispensations of human history (see D&C 128:18).” (Neal A. Maxwell, "God Will Yet Reveal," Ensign, Nov. 1986, p. 52)