The first part of Alma’s blessing dealt with Helaman’s duty to God. This part is his duty to his people. The first duty is to keep a record, as Alma has done. This refers to the large plates rather than the personal record on which this blessing was found. The large plates are the official record of the people, and those are now officially passed from Alma to Helaman. In addition to the charge to write, there is a charge to preserve. As record keeper, there was a dual responsibility to both create a record and to preserve the records that had been passed down.
One of the important records in the collection was the brass plates. They were the same plates that Nephi had taken from Laban in Jerusalem and which had come across the ocean. They preserved the genealogy of the forefathers, which was the link to the Old World and was probably considered to be one form of validation of the Nephite right to rule. These records were passed down through the kings or the official record keepers.
Verse 5 suggests that “if they are kept, they must retain their brightness.” Whether they are “bright” because of the doctrine they contain, or because they were cared for, or through some other means, the suggestion is that they were not tarnished by time. They were a record that was sacred not only for the text on them, but as a sacred artifact. In the Old World, Israel had the Arc of the Covenant containing important sacred relics. For the Nephites, the brass plates served that function, in addition to preserving the words of the Old World prophets.