The Atoning Messiah explains his future mission as the Triumphant Messiah at the end-time. Then he will judge the nations.
Reference: This passage echoes Revelation 7:9: “A great multitude, which no man could number, of all nations, and kindreds, and people, and tongues, stood before the throne, and before the Lamb, clothed with white robes, and palms in their hands.” The four-item list of people, kindreds, nations, and tongues certainly borrows the language of Revelation. The context of judgment also fits. Although 3 Nephi 26:4 does not quote Revelation 7:9, Joseph borrowed its vocabulary to translate the meaning recorded on the plates.