“God himself, the Father of us all, ordained and established a plan of salvation whereby his spirit children might advance and progress and become like him. It is the gospel of God, the plan of Eternal Elohim, the system that saves and exalts, and it consists of three things. These three are the very pillars of eternity itself. They are the most important events that ever have or will occur in all eternity. They are the Creation, the Fall, and the Atonement.
Before we can even begin to understand the temporal creation of all things, we must know how and in what manner these three eternal verities—the Creation, the Fall and the Atonement—are inseparably woven together to form one plan of salvation. No one of them stands alone; each of them ties into the other two; and without a knowledge of all of them, it is not possible to know the truth about any one of them.” – Elder McConkie, Christ and the Creation, Ensign, Jun 1982
“But, be it remembered, the Atonement came because of the Fall. Christ paid the ransom for Adam’s transgression. If there had been no Fall, there would be no Atonement with its consequent immortality and eternal life. Thus, just as surely as salvation comes because of the Atonement, so also salvation comes because of the Fall” – Elder McConkie, Christ and the Creation, Ensign, Jun 1982
“Just why the Lord would say to Adam that he forbade him to partake of the fruit of that tree is not made clear in the Bible account, but in the original as it comes to us in the Book of Moses it is made definitely clear. It is that the Lord said to Adam that if he wished to remain as he was in the garden, then he was not to eat the fruit, but if he desired to eat it and partake of death he was at liberty to do so” – President Joseph Fielding Smith, Answers to Gospel Questions, comp. Joseph Fielding Smith Jr., 5 vols. [1957–66], 4:81
“Adam and Eve came into this world to perform exactly the part they they acted in the garden of Eden; and I will say, they were ordained of God to do what they did, and it was therefore expected that they would eat of the forbidden fruit in order that man might know both good and evil by passing through this school of experience that this life affords us.” – President Wilford Woodruff, Journal of Discourses, 23:126
“The ‘Fall’ was as much a part of God’s earth-planned life for man as the ‘redemption’ provided for him… and no redemption would have been provided but for anticipation of the ‘Fall.’” – Elder B.H. Roberts, The Truth, the Way, the Life, BYU Religious Studies Center, p. 345
“The plan of redemption must start with the account of the fall of Adam…just as man does not really desire food until he is hungry, so he does not desire the salvation of Christ until he knows why he needs Christ. No one adequately and properly knows why he needs Christ until he understands and accepts the doctrine of the Fall and its effect upon mankind.” – President Ezra Taft Benson, “The Book of Mormon and The Doctrine and Covenants”, Conference Report, Apr 1987, p. 106
“One of these days, if I ever get to where I can speak to Mother Eve, I want to thank her for tempting Adam to partake of the fruit. He accepted the temptation, with the result that children came into this world. And when I kneel in prayer, I feel to thank Mother Eve, for if she hadn’t hand that influence over Adam, and if Adam had done according to the commandment first given to him, they would still be in the Garden of Eden and we would not be here at all…Brethren an sisters, let’s thank the Lord, when we pray, for Adam.” – President Joseph Fielding Smith, Conference Report, Oct 1967
Comparison of Adam and Christ found in The Lost Language of Symbolism by Alonzo L. Gaskill