(This is an excerpt from the chapter "The Strait and Narrow Path: The Covenant Path of Discipleship Leading to the Tree of Life" by Aaron Schade in the book Things Which My Father Saw: Approaches to Lehi's Dream and Nephi's Vision.)
In the Book of Mormon, the dreams and interpretations of partaking of the fruit of the tree of life seem to carry the same ritualistic connotations as they did in other ancient Near Eastern cultures. In 1 Nephi 8:21, Lehi states that he saw “numberless concourses of people, many of whom were pressing forward, that they might obtain the path which led unto the tree by which I stood.” This description highlights the fact that not all people were on the path and that significant effort was being exerted by concourses of people pressing forward just to obtain and get on it. Second Nephi 31:9, 15–21 describe the gateway that brings one onto the path and underscores the covenant nature underlying the process. Nephi, at the latter end of his life, discusses the essential nature of baptism and specifically draws upon motifs from the dream of the tree of life to incorporate how the Savior’s baptism “showeth unto the children of men the straitness of the path, and the narrowness of the gate, by which they should enter, he having set the example before them” and that “the gate by which ye should enter is repentance and baptism by water; and then cometh a remission of your sins by fire and by the Holy Ghost. And then are ye in this strait and narrow path which leads to eternal life; yea, ye have entered in by the gate; ye have done according to the commandments of the Father and the Son” (2 Nephi 31:9, 17–18; emphasis added).
Elder L. Tom Perry further clarifies the concept that baptism, both by water and by fire, gets one on the path:
The ordinance of baptism by water and fire is described as a gate by Nephi (see 2 Nephi 31:17). Why is baptism a gate? Because it is an ordinance denoting entry into a sacred and binding covenant between God and man. Men promise to forsake the world, love and serve their fellowmen, visit the fatherless and the widows in their afflictions, proclaim peace, preach the gospel, serve the Lord, and keep His commandments. The Lord promises to “pour out his Spirit more abundantly upon [us]” (Mosiah 18:10), redeem His Saints both temporally and spiritually, number them with those of the First Resurrection and offer life eternal. Baptism and receiving the Holy Ghost are the prescribed ways to enter the strait and narrow path to eternal life.
This statement describes the path as a covenantal road that leads to the tree of life and makes it clear that it is entered through baptism. Second Nephi 31:19–21 then describes the necessity of traversing the path and enduring to the end by feasting upon the word of Christ (holding the iron rod), as there is no other name or way given to obtain eternal life. In 2 Nephi 33:6–7, 9, Nephi glorifies in Christ, who has redeemed his soul from hell, and describes his charity and hope for others as they also become reconciled unto Christ, enter into the narrow gate, and endure in the strait path leading to eternal life.
Elder McConkie expounded upon the principle of entering and pressing forward on the covenantal path:
As far as you and I are concerned, at this time, this life is the most important part of all eternity. We have the light and knowledge and revelations of heaven. This life is the time for us to prepare to meet God, to keep the commandments of God, to hearken to the counsels of the living oracles and to press forward in righteousness.
The plan of salvation is to find the truth; and the Latter-day Saints have found it. It is to accept the truth; and we have accepted it in the waters of baptism by covenant, a covenant that we will keep the commandments of God. The remaining step is to endure to the end, in righteousness and in faithfulness. Nephi said that repentance and baptism are the gate to salvation, and that having entered in by the gate, men are then in the straight and narrow path which leads to eternal life. We Latter-day Saints have entered in by the gate. We are now on the path. It remains for us to press forward with a steadfastness in Christ, having a perfect brightness of hope, and a love of God and of all men. It remains for us to press forward, feasting upon the words of Christ, and endure to the end, which if we do, we will gain eternal life.