From Concerning The Divine Wisdom ~ Emanuel Swedenborg
All things of the body, both internal and external, are correspondences.What correspondence is has not hitherto been known in the world, for the reason that it has not been known what the spiritual is, and that there is a correspondence between what is natural and what is spiritual. When anything from the spiritual as the origin and cause becomes visible and perceptible before the senses, there is a correspondence between them. There is such a correspondence between spiritual and natural things with man
Because these have existed and perpetually exist, that is, subsist from spiritual things, they are correspondences; and therefore the two act as one, like end, cause, and effect. Thus the face acts as one with the affections of the mind, the speech with the thought, and the actions of all the members with the will; and the same is true of other things.Spiritual things are all things pertaining to his love and wisdom, consequently to his will and understanding.
Natural things are all things pertaining to his body.
It is a universal law of correspondences that the spiritual fits itself to use, which is its end, and actuates and modifies the use by means of heat and light, and clothes it by provided means, until there results a form subservient to the end; and in this form the spiritual acts as the end, use as cause, and natural as effect; although in the spiritual world the substantial takes the place of the natural.All things that are in such forms.
(Divine Wisdom II:3)