This introduction is not meant to teach a particular type of doctrine, but it reveals some details about Mormon’s beliefs. First, he differentiates between God the Father and “his Holy Child, Jesus.” Pre-visitation Nephite theology had not explicitly made this differentiation. (See “Excursus: The Nephite Understanding of God,” following 1 Nephi 11.)
Second, this benediction assumes the Messiah’s existence and the effect of the achieved atonement—namely, the Savior’s “infinite goodness and grace.” Mormon does not go into the details of the two deaths from which humankind must be saved (2 Ne. 9:12; Alma 12:16, 42:7–9; Hel. 14:16). Rather, he emphasizes faith, a stronger theme after the atonement than before.
Mormon’s introduction, in other words, assumes a post-visitation theology. He is not explaining those doctrines but simply assuming them. Obviously they form the basis of Mormon’s beliefs, and he just as obviously assumes that his son will understand this introduction without needing any explanation.