And now behold, I say unto you that if it had been possible for Adam to have partaken of the fruit of the tree of life at that time, there would have been no death, and the word would have been void, making God a liar, for he said: If thou eat thou shalt surely die.
And we see that death comes upon mankind, yea, the death which has been spoken of by Amulek, which is the temporal death; nevertheless there was a space granted unto man in which he might repent; therefore this life became a probationary state; a time to prepare to meet God; a time to prepare for that endless state which has been spoken of by us, which is after the resurrection of the dead.-- Alma 12:23-24.
At the April 1995 general conference, Elder M. Russell Ballard of the Quorum of the Twelve said: "Through prophets past and present, God has revealed the doctrines of His 'great plan of happiness.' It consists of infinite, eternal, absolute, unchanging principles. From Alma we learn that 'God gave unto them commandments, after having made known . . . the plan of redemption.' (Alma 12:32). The plan teaches that all who have or will live on earth are the spirit children of heavenly parents. We lived with them before coming to this earth to receive our bodies of flesh and bone.
" 'If Adam [and Eve] had not transgressed [they] would not have fallen, but [they] would have remained in the garden of Eden. . . . And they would have had no children; wherefore they would have remained in a state of innocence, having no joy. . . . Adam fell that men might be; and men are, that they might have joy.' " (2 Nephi 22-23, 25.)
Elder Ballard said that the Father's plan provides redemption from the Fall through the atonement of Jesus Christ. "As the Only Begotten Son of God and the only sinless person who lived on this earth, He made a perfect atonement for all mankind," Elder Ballard said. "It applies to everyone unconditionally as it pertains to the resurrection from temporal, or physical, death, for all shall rise from the dead with immortal bodies as a result of the Atonement. However, the Atonement is conditional as it pertains to each person's individual sins. It touches everyone to the degree that he or she has faith in Jesus Christ, repents, and obeys the gospel. Exaltation and eternal life with God are reserved for those who keep the commandments.
"Mortality, then, is the time to test our ability to understand our Heavenly Father's plan and, of course, our willingness to be obedient. Obedience is essential to obtain exaltation and eternal life."