In 3 Nephi 8:1 we find a statement that on first glance might not be understood to its fullest. Mormon, is speaking, but from a covenant perspective. There are certain words that should tip the reader off that this is so. One of those words is "know." It means much more than intellectual knowledge. It means knowledge gained by obedience to covenants with the Lord, and affirmed by the Spirit of the Lord. Mormon states:
And now it came to pass that according to our record, and WE know our record to be true, for behold, it was a just man who did keep the record--for he truly did many miracles in the name of Jesus; and there was not any man who could do a miracle in the name of Jesus save he were cleansed every whit from his iniquity--
Mormon is referring here to the first record keeper, "Nephi, the son of Nephi, who was the son of Helaman" (see the Title to 3 Nephi), as a "just" man made perfect in Christ. To be a "just man made perfect in Christ" is not only a covenant process, but a process with which Mormon is apparently familiar because he joins his own witness to that of Nephi in saying, "WE know our record to be true." [Alan C. Miner, Personal Notes] [See the commentary on 1 Nephi 3:7]