For example, there are societies that perform the function of welcoming spirits into the spiritual world when they die. We're told that those are the spirits in the society corresponding to the mouth. There are spirits who are in love more than in anything else and they're in the society corresponding to the heart. There are others who are in the love of truth. They represent the lungs, and so on.
Every angel has a different function or use.
Every society has these different functions. The body itself is held together and protected by a skin. Now the skin, people sometimes forget, is the largest organ in the body. It's the most obvious and the one we think of least. The body of the church on earth is held together by its skin which is its external order and organization.