Mormon 7:9

"For behold, this is written for the intent that ye may believe that; and if ye believe that ye will believe this also; and if ye believe this ye will know concerning your fathers, and also the marvelous works which were wrought by the power of God among them."

The Book of Mormon (this) and Bible (that) are complementary. If you really believe the Bible, you will also believe the Book of Mormon. Reading both books helps us understand the history of prophets and the miracles wrought by God's power in past days. I am so grateful to have both books of scripture today.