Arcana Coelestia #126
126. Verse 17 But from the tree of the knowledge of good and evil, you shall not eat of it, for on the day that you eat of it you will surely die. Taken with those that precede them, these words mean that it is allowable, by means of every perception obtained from the Lord, for anyone to discover what truth and good are, but it is not allowable to do so from self and the world, that is, to probe into mysteries of faith by means of sensory evidence and factual knowledge. If he does the celestial in him dies.
Soul
The nature of the soul is a deep and complicated topic, but it can be summarized as our spiritual life — that is, who we are in terms of our thoughts and affections. And that, generally, is the internal sense when the Bible talks of a soul. You could be missing limbs, disfigured in the body due to illness or accident, paralyzed, but you would still be a complete human being. That's because the soul is the real you, and the soul has to do with internal things, not the state of your body.