20 And also that we may preserve unto them the words which have been spoken by the mouth of all the holy prophets, which have been delivered unto them by the Spirit and power of God, since the world began, even down unto this present time.
Here is the second main reason why retrieving the Brass Plates was so critical. They contained the “words of all the holy prophets . . . since the world began . . .” The scriptures contain the word of God as spoken by his prophets. D&C 1:37—38 says that we should search the commandments because the words of the prophets are the words of God. Amos 3:7 tells us that before God does anything pertaining to us He first “revealeth his secret unto his servants the prophets.” So not only are the words of God given through prophets, before He does anything to or with his people, He first tells or warns his prophets. That’s why it was so important that Lehi take the scriptures. The purity of the Gospel had to be preserved in writing rather than relying on memory from generation to generation. It’s just so important to be able to go back to the original intent of the author rather than rely on personal memory interpretation, which is what would happen if we didn’t have written scriptures.