Was Adam's spirit annihilated when he sinned, or was it just dormant?
Adam's spirit was not annihilated when he sinned. It died in the sense of lost fellowship with the Creator, yet it remained present but dormant—like a tree in winter or a run-down car battery—dead and unable to restore itself until outside energy regenerates it.
Les explains that Adam was created with body, soul, and spirit, and his spirit was the part by which he had fellowship and communion with the Creator. When Adam sinned, God's warning that he would surely die was fulfilled spiritually, not physically, since Adam lived 939 more years. His spirit did not completely disappear but died and became dormant—like a tree in winter or a run-down car battery. It remained present but dead, unable to recover until outside energy comes in and regenerates it. At the same time, Adam's created personality became a sin nature, the old Adam, bent only toward rebellion against everything God instructed.