It is allotted the highest place in the human mind. Below itself it sees civic concerns that relate to the world. In fact, it rises up through these concerns the way the purest sap rises up through a tree to its very top, and surveys from that height the earthly things that lie below, the way someone looks down from a tower or a high point of land onto the fields below.
It is important to note, however, that our understanding can rise up almost into the light that the angels of heaven have, but if our will does not rise along with it, we are still the old self, not the new self. (I have already shown how the understanding lifts the will up with itself, higher and higher.)
For this reason, regeneration is primarily a matter of the will, and only secondarily a matter of the understanding. The understanding in us is like light in the world, and our will is like the heat here. Without heat, light brings nothing to life and makes nothing grow; as we know, light has to act in partnership with heat. The understanding that is in the lower part of the mind is actually in the light of this world; the understanding that is in the higher part of the mind is in the light of heaven.
Therefore if our will is not lifted up from the lower region into the higher region to join the understanding, it remains at the level of the world. Then our understanding flies up and down, up and down. Every night, though, it flies down and sleeps with our will below, and the two make love like a married man and a whore and bring forth two-headed offspring.
from Regeneration, Page 71