Mormons believe in a preexistence, where spirts once existed in what is known as the First Estate. Ecclesiastes 12:7 says, in part, that “the spirit shall return unto God who gave it.” This poetic book is describing how the body decomposes to “dust” and the spirit returns to God for judgment; this does not imply a preexistent state. Zechariah 12:1 states that God forms “the spirit of man within him.” The assumption is not that man was composed solely of spirit in some premortal state but that man has a physical body in which the spirit dwells.
Many Mormons point to the church fathers for support of this doctrine. While it is true that Origen (185–254) advocated a type of preexistence, historians consider this view to be mere speculation. One church historian wrote,
“Origen tried to express the Christian faith in terms of the prevailing Platonic philosophical ideas of his time. Some of his speculations, for example about the pre-existence of souls and universal salvation, were repudiated by the church, and helped bring about his later condemnation.” (Everett Ferguson, “Origen,” in Dowley and Alexander, The History of Christianity, 107)
“The problem is that Origen was very much enamored with speculation and it sometimes led to conclusions that seem patently unbiblical. . . . According to Origen, this premortal, spiritual probation explains why humans enter the world in such unequal conditions. It is his own form of what some Eastern religions call ‘karma.’ Such speculation seemed innocent and even helpful to Origen, but it goes far to explain why some other Christians regarded him as a heretic.”(Olson, The Sotry of Chrsitian Theology, 104)
Origen even admitted that his ideas were his own and not necessarily canonical. (Gonzales, The Story of Christianity, 1:79-80) In addition, Origen’s teaching is not even close to Mormonism’s doctrine of premortality. For example, he did not teach that Jesus was the firstborn offspring of God or that humans are the siblings of Jesus. The doctrine of premortality is nothing more than mere speculation on behalf of the Mormon leadership. With no evidence from the Bible, this doctrine is soundly rejected by Bible-believing Christians.
While the Bible does show how all humans are creations of God, becoming a part of His family requires faith in the redemptive work of Jesus Christ. Paul writes in Galatians 3:26, “For ye are all the children of the flesh who are the children of God, but the children of the promise are counted as offspring.” (ESV) Even the Book of Mormon tends to discount the idea of preexistence. Ether 3:14 says, “Behold I am Jesus Christ. I am the Father and the Son. In me shall all mankind have life, and that eternally, even they who shall believe on my name; and they shall become my sons and my daughters.” A Mormon may argue that this only refers to a spiritual sonship. However, this objection has validity only if it can be demonstrated that the Book of Mormon teaches the LDS concept of the preexistence, which it does not.
See Jeremiah 1:5.