The title “God” in the Nephite record first carries the Old Testament sense of Yahweh, the God of Abraham, Isaac, and Jacob, the figure Jesus identifies himself with when he tells the Jews, “Before Abraham was, I am” (John 8:58). The distinction between the Father and the Son, and between Jesus and his own Father, is disclosed gradually across the record.
Nephi calls Christ “the Only Begotten of the Father,” who “shall manifest himself unto them in the flesh,” pointing to a coming incarnation (2 Nephi 25:12). His account of the doctrine of Christ assigns roles to both the Father and the Son in baptism and obedience: the Son humbles himself before the Father and keeps his commandments, the Father commands repentance and baptism in the name of the Son, and the Holy Ghost witnesses of both, the three being “one God, without end” (2 Nephi 31:7-21).
Abinadi teaches that God himself comes down among men as the Son: Christ is the Father because he was conceived by the power of God, and the Son because of the flesh, the flesh being subject to the Spirit, so that the two are one God, “the very Eternal Father of heaven and of earth” (Mosiah 15:1-5).
When Christ appears and teaches among the Nephites, he speaks as distinct from the Father while conveying the Father’s will and words to the people, and prays to the Father in their presence, showing separate persons of shared divinity and one purpose (3 Nephi 16, 20, 21, 24).
In the later record, Mormon and Moroni describe the Father, the Son, and the Holy Ghost as one Godhead with distinct persons and functions, drawing together the earlier Nephite teachings on the nature of God.