The path of Nephi’s exegesis began with a discussion of the Jews, and their future redemption through the acceptance of the Messiah. In the context of the salvation of the Jews, Nephi has now discussed his own people, precisely because he includes himself and his people (and also the Lamanites, though only in the far distant future) as involved in the prophesies of the redemption of the Jews.
Having finished with his explanation of the need for the Jews (and the subset of the Nephites and Lamanites) to accept the Savior. He now explicitly turns to the gentiles, and specifically notes that they also must equally accept that “Jesus is the Christ, the Eternal God.” This is a requirement of all the world, although the fulfillment of that requirement will come in different times and ways.