Also, I have wondered about our progression before we are born. We have lived forever as I understand it. What have we been doing all that time? Do you think we may have been living other lives on other planets or other Earths? Or perhaps living past lives on this earth by our own choice for learning or progression? We definitely had to have past lives in some form or other to have existed forever. Just wondering what your insight is into this?
Reincarnation is a false doctrine. There is only one mortal existence per person. The ancient apostle testified, “it is appointed once unto man to die” (Hebrews 9:27). In the narrowest sense, this is the definition of “life” and as such, we cannot speak of past lives rationally. Not on this earth. Not on other earths.
Words are funny though. “Life” has also the meaning of a discreet existence, usually with specific start and end points. For instance, I may speak of my life as a pilot. There was a distinct start when I flew my first plane, and a distinct end when I am no longer able to do so. I may also speak of my life as gramps, which has a distinct start, with a distinct unattained end (when I cease grampsing). Many such periods could be spoken of as such, but it is not in our popular vernacular to speak of living multiple “lives” during a single mortal sojourn (except euphemistically for a person with an especially accomplished life).
In this same sense, Latter-day Saints speak of a “pre-mortal life”, which began when we were organized and ended with a mortal birth. Similarly, we may speak of a “new life” in Christ beginning with a conversion, being born again (birth itself serving as a metaphor for this fresh start), which ends only in apostasy (the best stories have no end). Ultimately, we seek that eternal life promised the faithful. In all this though, we don’t speak of having multiple “lives”, but recognize that such existences hinge on choices we make to enter and exit them.