As answer to the possible doubts, Jesus now self-identifies. He has been introduced by his Father, he now proclaims himself. He is Jesus the Messiah.(Monte S. Nyman. “The Designations Jesus Gives Himself in 3 Nephi.” Monte S. Nyman and Charles D. Tate, Jr., eds., Third Nephi 9-30: This Is My Gospel [Provo: BYU Religious Studies Center, 1993], 43.) At this point we must remember that Christ is a title, the Greek form having the same meaning as the word Messiah that we receive through the Hebrew rather than the Greek. Jesus is identifying himself, and his title to these people. This is absolutely important, as they have been awaiting the Messiah. Jesus is declaring that it is he for whom they have been waiting. It is he about whom they were just discussing.
The fulfillment of hundreds of years of prophecy now stands before them, miraculously descended from heaven before their eyes.