The reason the spiritual world’s sun appears at a distance from angels is that they accept divine love and wisdom at an appropriate level of warmth and light. Since angels are created and finite, they cannot accept the Lord at the prime level of warmth and light, as it is in the sun. That would mean being totally consumed; so they accept the Lord at the level of warmth and light that matches their own love and wisdom.
The following may serve to illustrate. Angels of the lowest heaven cannot rise up to angels of the third heaven. If they were to rise up and enter their heaven, they would collapse in a kind of faint, as though their life were struggling against death. This is because their love and wisdom is at a lower level, and so is the warmth of their love and the light of their wisdom. What would happen, then, if an angel were to rise up toward the sun and enter its fire?
As a result of the differences in angels’ acceptance of the Lord, the heavens appear to be marked off from each other. The highest heaven, called the third heaven, seems to be over the second, and the second over the first. It is not that the heavens are distant from each other, but that they seem to be. In fact, the Lord is just as present with people in the most remote heaven as he is with people in the third heaven. What causes the appearance of distance is in the subjects, the angels, and not in the Lord.
It is almost impossible to grasp this in any earthly image, since that would involve space. It can be grasped in a spiritual image, though, since there is no space involved. That is the kind of image angels have.
This much can be grasped in an earthly image, though—love and wisdom, or in other words the Lord who is divine love and wisdom, cannot move through space but is with every one of us depending on our acceptance. The Lord teaches in Matthew 28:20 that he is with everyone; and in John 14:21 [14:23] he says that he makes his home with those who love him.
This may seem like a matter of higher wisdom since it is being supported by reference to heavens and angels. However, the same holds true for us. As far as the deeper levels of our minds are concerned, we are warmed and enlightened by that same sun, warmed by its warmth and enlightened by its light, to the extent that we accept love and wisdom from the Lord. The difference between angels and us is that angels are under that [spiritual] sun only, while we are not only under that sun but also under the sun of our world. Our bodies could not take form and endure if they were not under both suns. It is different for angels’ bodies because they are spiritual.
from Divine Love and Wisdom, Sections 110-112