The following information is summarized from the page ”Becoming Like God” in the Gospel Topics section of LDS.org (topics.lds.org).

Latter-day Saints see all people as children of God in a full and complete sense; they consider every person divine in origin, nature, and potential. Each has an eternal core and is “a beloved spirit son or daughter of heavenly parents.” Each possesses seeds of divinity and must choose whether to live in harmony or tension with that divinity. Through the Atonement of Jesus Christ, all people may “progress toward perfection and ultimately realize their divine destiny.” (See The Family: A Proclamation to the World) Just as a child can develop the attributes of his or her parents over time, the divine nature that humans inherit can be developed to become like their Heavenly Father’s.

Latter-day Saints believe that men and women have the potential to be exalted to a state of godliness to live as God lives, to love as He loves, and to prepare for all that our loving Father in Heaven wishes for His children. Our progression will never change His identity as our Father and our God. God’s children will always worship Him.

This belief is founded in Biblical teachings. For example, the Apostle Paul taught that we are “the offspring of God” and emphasized that as such “we are the children of God: and if children, then heirs; heirs of God, and joint-heirs with Christ.” (Acts 17:29; Romans 8:16–17) The book of Revelation contains a promise from Jesus Christ that “to him that overcometh will I grant to sit with me in my throne, even as I also overcame, and am set down with my Father in his throne” (Revelation 3:21).

Latter-day revelations received by Joseph Smith clarify these scriptures as straightforward expressions of humanity’s divine nature and potential. These revelations teach that humans are created in the image of God and that God cares intimately for His children. God desires that His children receive the same kind of exalted existence of which He partakes. As God declared, “This is my work and my glory—to bring to pass the immortality and eternal life of man” (Moses 1:39).

Section 76 of the Doctrine and Covenants records a vision where Joseph Smith and Sidney Rigdon saw the afterlife. In the vision, they learned that the just and unjust alike will receive immortality through a universal resurrection, but only those “who overcome by faith, and are sealed by the Holy Spirit of promise” would receive the fulness of God’s glory and be “gods, even the sons of God” (D&C 76:53, 58). Another revelation confirmed that “the saints shall be filled with his glory, and receive their inheritance and be made equal with him” (D&C 88:107). 

In section 132 of the Doctrine and Covenants , the Lord declared that those who keep covenants, including the covenant of eternal marriage, will inherit “all heights and depths.” “Then,” says the revelation, “shall they be gods, because they have no end.” They will receive “a continuation of the seeds forever and ever” (D&C 132:19–20).

The April 1844, Joseph Smith delivered a sermon about the nature of God to the Saints who had gathered for a general Church conference. He used the occasion in part to reflect upon the death of a Church member named King Follett, who had died unexpectedly a month earlier. “What kind of a being is God?” he asked. Human beings needed to know, he argued, because “if men do not comprehend the character of God they do not comprehend themselves.” God “was once as one of us” and “all the spirits that God ever sent into the world” were likewise “susceptible of enlargement.” Joseph Smith preached that long before the world was formed, God found “himself in the midst” of these beings and “saw proper to institute laws whereby the rest could have a privilege to advance like himself” and be “exalted” with Him. (See “Becoming Like God,” footnotes 34-36.)

Since that sermon, known as the King Follett discourse, the doctrine that humans can progress to exaltation and godliness has been taught within the Church. Lorenzo Snow coined a well-known couplet: “As man now is, God once was: As God now is, man may be” (Eliza R. Snow, Biography and Family Record of Lorenzo Snow, 46). Little has been revealed about the first half of this couplet, and consequently little is taught. When asked about this topic, Church President Gordon B. Hinckley told a reporter in 1997, “That gets into some pretty deep theology that we don’t know very much about.” When asked about the belief in humans’ divine potential, President Hinckley responded, “Well, as God is, man may become. We believe in eternal progression. Very strongly.” (See “Musings of the Main Mormon,” Don Lattin, San Francisco Chronicle, Apr. 13, 1997; see also David Van Biema, “Kingdom Come,” Time, Aug. 4, 1997, 56.)

Eliza R. Snow, a Church leader and poet, wrote a poem that later became the hymn “O My Father” (Hymns, no. 292). She explained that we are children of a Heavenly Father and a Heavenly Mother. Elder Dallin H. Oaks explains that “Our theology begins with heavenly parents. Our highest aspiration is to be like them” (“Apostasy and Restoration,” Ensign, May 1995, 84).

All human beings are children of loving heavenly parents and possess seeds of divinity within them. Our divine nature and potential for exaltation have been repeatedly taught in general conference addresses, Church magazines, and other Church materials. “Divine nature” is one of eight core values in the Church’s Young Women program. Teaching on human beings’ divine parentage, nature, and potential features prominently in “The Family: A Proclamation to the World.” Divine nature and exaltation are essential and beloved teachings in the Church.

For a more thorough explanation, along with historical context, see “Becoming Like God.” That article in the Gospel Topics section of LDS.org explains additional teachings about our eternal relationship with God and our understanding of exaltation. In the right margin on that page, note the references to read what latter-day prophets have taught about becoming like God.