One of the most distinctive beliefs in Latter-day Saint doctrine is captured in a couplet by Lorenzo Snow:
As Man is, God once was. As God is, man may become.
Lorenzo Snow
While the idea of God’s incarnation, specifically in the person of Jesus Christ, is nothing new in Christianity, Latter-day Saint doctrine goes further to claim that God the Father was once a human like us. This differs significantly from the Christian Trinity, in that the Father is an unchangeable spirit from everlasting to everlasting.
Latter-day Saint doctrine also teaches that humans who receive all the ordinances and covenants in the Temple, and remain worthy until the end, will become Gods.
This Gospel Topics Essay published by the Church attempts to explain Latter-day Saint doctrines about how humans can become [like] God.