(This is an excerpt from the chapter "Not Partaking of the Fruit: Its Generational Consequences and Its Remedy" by Matthew L. Bowen in the book Things Which My Father Saw: Approaches to Lehi's Dream and Nephi's Vision.)
Adam and Eve’s choice to partake of the fruit of the tree of the knowledge of good and evil had enduring consequences for themselves and their posterity. Similarly, Laman and Lemuel’s choice not to partake of the tree of life resulted in long-lasting bitter consequences for themselves and their posterity. In both instances, the consequence of the decision was being “cut off” or “cast off” from the presence of the Lord. Adam and Eve subjected their posterity to physical death; Laman and Lemuel subjected generations of their posterity to spiritual death.
The generational consequences of Laman and Lemuel’s unwillingness to partake seem to have been uppermost in Lehi’s mind when he related his vision of the tree of life to his family. Nephi prefaces the account with his father’s statement, “But behold, Laman and Lemuel, I fear exceedingly because of you” (1 Nephi 8:4). Nephi punctuates the account with two summative comments: “And Laman and Lemuel partook not of the fruit, said my father,” (v. 35; emphasis in all scriptural citations is mine) and “he exceedingly feared for Laman and Lemuel; yea, he feared lest they should be cast off from the presence of the Lord” (v. 36).
The statements “Laman and Lemuel, I fear exceedingly because of you” (v. 4) and “he exceedingly feared for Laman and Lemuel” (v. 36) constitute a framing device known as an inclusio, or envelope figure. This framing repetition places the entire dream in the context of Lehi’s fear for his sons, their families, and their families’ posterity: Laman and Lemuel were choosing not to partake of the fruit of the tree of life, which would inevitably lead to their being cut off from the Lord’s presence. As Lehi knew, this was the “curse” that would—like the consequences of the Fall—be passed on to their posterity and perpetuated for generations (see Alma 3:19; 2 Nephi 4:3–9, especially vv. 5–6).
Nephi’s twofold declaration that he saw “the things which [his] father saw” (1 Nephi 11:3; 14:29) provides a similar inclusio for his own vision, a framework which recommends 1 Nephi 11–14 as a reliable guide for interpreting Lehi’s vision and his exceeding fear for Laman and Lemuel. Nephi explicitly states that he saw his posterity and the posterity of his brothers, who eventually overpowered his own descendants (1 Nephi 12:19). He was then told by his angelic guide that “these [would] dwindle in unbelief” (v. 22), and he saw the far-reaching cultural and spiritual consequences of this unbelief on his brothers’ posterity (v. 23; see also 2 Nephi 5). ...
The Book of Mormon is not only a chronicle of the tragic consequences of choosing unbelief, but also powerful evidence of the fruits of faith. Faithfulness—enduring and unshakeable faith in Jesus Christ—emerges as the only means of remedying the generational consequences of unbelief, a remedy which sometimes has its desired effect only after long periods of time. The faithfulness of Lehi, Nephi, Jacob, Enos, and the holy men who followed (whose faith was typical of the faith of the patriarchs and ultimately of the Savior himself) eventually helped reverse the consequences of Laman and Lemuel’s choice. Their examples emerge as ones fully worthy of our emulation. Although the tragic final chapters of Mormon’s history suggest that he constructed his story to show the final and complete fulfillment of Lehi’s and Nephi’s visions, his record and the record on the small plates show how the Lord’s people are to help remedy the almost universal sin of unbelief, so that “faith . . . might increase in the earth” (D&C 1:21) and eventually prevail (see Jacob 5:66, 75).