Elven Deity Mythos

According to legend, the first elves (primal Feywild elves) were made by a deity, and they eventually had a disagreement with the deity and became the modern elf races we know today. Angered by their schism, the deity banned their souls from spending eternity in the afterlife until he was ready to forgive them. 
When elves die, they are judged by the deity, and if not found worthy, they get to spend some time in the afterlife but are soon reincarnated to live another life and essentially try again. So all elves have been reincarnated many times, but their memories are blocked. 
When an elf goes into their trance at rest time, they don't dream but they relive past experiences of their lives. This marks adulthood, when a young elf switches from reliving their time in the afterlife to reliving their life experiences.
According to this belief, and elf has reached adulthood when they switch from reliving their time in the afterlife to their current life. An elf is reaching their elder stage in life when they begin to occasionally relive memories from previous reincarnations.
This belief is held to varying degrees within the elven communities in present day.