Moroni's promise is perhaps the best known, most frequently quoted scripture in the entire Book of Mormon. It is the closing witness of a prophet of God. The truth of the book rests on his simple, sublime assurance. He gives us the key to open the door of light and truth: a sincere heart and real intent. Seldom will a person who approaches the Book of Mormon with a skeptical mind or a desire to prove it false come away with the witness that is delivered by the sweet whisperings of the Spirit to a humble and honest seeker. It is by the power of the Holy Ghost that we know when something is true or not. It is b the power of the Holy Ghost that we can have discernment. If we sincerely seek, humbly ask, and truly desire with all our hearts to know the truth, we will find it within the pages of this sacred scripture.
When Ye Shall Receive These Things, p 392