The number "four" in the Bible represents things being linked together or joined. This is partly because four is two times two, and two represents the ultimate linking between our desire to be good and our understanding of truth. We can also see this in the fact that most buildings are rectangular, with the four sides linking together to make a whole. We also divide directions into four -- north, east, south and west -- and talk about the "four corners" of something meaning all of it. So our special thinking naturally looks at four sides as linking together into a whole.

(Verweise: Apocalypse Explained 417; Arcana Coelestia 1686, 9103, 9601, 9767, 9864)

19. The presence of infinite things in God is even more obvious to angels because of the heavens where they live. The whole heaven, made up of millions of angels, is like a person in its overall form. Each individual community of heaven, large or small, is the same; and therefore an angel is a person. An angel is actually a heaven in its smallest form (see Heaven and Hell 51-87 [51-86]).

Heaven is in this form overall, regionally, and in individuals because of the divine nature that angels accept, since the extent to which angels accept the divine nature determines the perfection of their human form. This is why we say that angels are in God and that God is in them, and that God is everything to them.

The multiplicity of heaven is indescribable; and since it is Divinity that makes heaven, and therefore Divinity is the source of that indescribable multiplicity, we can see quite clearly that there are infinite things in that quintessential Person who is God.