President Ezra Taft Benson gave three reasons for studying the Book of Mormon
"The first is that the Book of Mormon is the keystone of our religion. This was the Prophet Joseph Smith’s statement. He testified that “the Book of Mormon was the most correct of any book on earth, and the keystone of our religion” (Introduction to the Book of Mormon). A keystone is the central stone in an arch. It holds all the other stones in place, and if removed, the arch crumbles.
"The second great reason why we must make the Book of Mormon a center focus of study is that it was written for our day. The Nephites never had the book; neither did the Lamanites of ancient times. It was meant for us. Mormon wrote near the end of the Nephite civilization. Under the inspiration of God, who sees all things from the beginning, he abridged centuries of records, choosing the stories, speeches, and events that would be most helpful to us.
"The third reason why the Book of Mormon is of such value to Latter-day Saints is given in the same statement by the Prophet Joseph Smith cited previously. He said, “I told the brethren that the Book of Mormon was the most correct of any book on earth, and the keystone of our religion, and a man would get nearer to God by abiding by its precepts, than by any other book” (History of the Church, 4:461). That is the third reason for studying the book. It helps us draw nearer to God. Is there not something deep in our hearts that longs to draw nearer to God, to be more like Him in our daily walk, to feel His presence with us constantly? If so, then the Book of Mormon will help us do so more than any other book.
"...President Marion G. Romney, ...who knows of himself of the power that resides in this book, testified of the blessings that can come into the lives of those who will read and study the Book of Mormon. He said:
“I feel certain that if, in our homes, parents will read from the Book of Mormon prayerfully and regularly, both by themselves and with their children, the spirit of that great book will come to permeate our homes and all who dwell therein. The spirit of reverence will increase; mutual respect and consideration for each other will grow. The spirit of contention will depart. Parents will counsel their children in greater love and wisdom. Children will be more responsive and submissive to the counsel of their parents. Righteousness will increase. Faith, hope, and charity—the pure love of Christ—will abound in our homes and lives, bringing in their wake peace, joy, and happiness” (Ensign, May 1980, p. 67)."
(The Book of Mormon--Keystone of Our Religion, By Ezra Taft Benson, President of the Church, October General Conference, 1986)