The reason so many varied elements act as one in an individual is that there is nothing whatever there that does not contribute something to the common good and do something useful. The inclusive body serves its parts and the parts serve the inclusive body because the inclusive body is made up of parts and the parts make up the inclusive body. So they provide for each other respectively, they focus on each other mutually, and they are united in the kind of form that gives every single component a relationship to the inclusive entity and its well-being. This is what enables them to act as a unit.
It is the same with assemblies in the heavens. People there unite in this kind of form in pursuit of any worthwhile activity. As a result any individuals who do not serve some use for the larger body are cast out of heaven because they are misfits. To “serve some use” is to intend well to others for the sake of the common good, while “not to serve some use” is to intend well to others not for the sake of the common good but for the sake of oneself. People who act in this latter fashion are people who love themselves above all, while people who act in the former fashion are the ones who love the Lord above all. This is why people in heaven act in unison not from themselves but from the Lord. They in fact focus on him as the unique source of all, and on his kingdom as the commonwealth that is to be cared for. This is the meaning of the Lord’s words, “Seek first the kingdom of God and his righteousness, and everything will be given you in addition” (Matthew 6:33). To “seek his righteousness” is to seek his good.
There are people who in this world love the good of their country more than their own and the good of their neighbor as their own. They are the ones who love and seek the kingdom of the Lord in the other life, since there the kingdom of the Lord takes the place of one’s country. Further, people who love to do good to others not for self-centered reasons but for the sake of the good itself are people who love their neighbor, since in the other life the good is one’s neighbor.d All individuals who are of this quality are in the universal human—that is, in heaven.
Since heaven in its entirety does reflect a single individual, and is in fact the divine spiritual person in its greatest form and image, heaven is therefore differentiated into members and parts like a person, and these are given similar names. Angels know what member one community or another is in and say that this community is in the member or province of the head, that one in the member or province of the chest, that one in the member or province of the genitals, and so on.
In general, the highest or third heaven forms the head down to the neck, the middle or second forms the torso as far as the genitals and knees, and the lowest or first forms the feet to the very soles and also the arms all the way to the fingers, since the arms and hands are among our “lowest things” even though they are at our sides. We can see from this again why there are three heavens.
from Heaven and Hell, Sections 64, 65