Alchemical Studies (Collected Works of C.G. Jung Vol.13)
Paracelsus says of the lumen naturae:
“Look at Adam and Moses and others.
They sought in themselves what was in man and have revealed it and all kabbalistic arts and they knew nothing alien to man neither from the Devil nor from the spirits, but derived their knowledge from the Light of Nature.
This they nurtured in themselves … it comes from nature which contains its manner of activity within itself. It is active during sleep and hence things must be
used when dormant and not awake—sleep is waking for such arts—for things have a spirit which is active for them in sleep.
Now it is true that Satan in his wisdom is a Kabbalist and a powerful one.
So, too, are these innate spirits in man . . . for it is the Light of Nature which is at work during sleep and is the invisible body and was nevertheless born like the visible and natural body.
But there is more to be known than the mere flesh, for from this very innate spirit comes that which is visible . . . the Light of Nature which is man’s mentor dwells in this innate spirit.”
Paracelsus also says that though men die, the mentor goes on teaching (Astronomia magna, ed. Sudhoff, XII, p, 23; “De podagricis,” ed. Huser, I, p. 566).
~Paracelsus, CW 13, Pages 113-114, Footnote 6.