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.

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

47. That these words contain arcana concerning regeneration becomes additionally clear from the fact that verse 24 above spoke of the earth bringing forth 'living creatures, beasts, and wild animals of the earth', while in the verse that followed the order was different, namely that God made the wild animals of the earth first and then the beasts. Indeed a person does first produce things so to speak from himself, and continues to do so until he becomes celestial. And so regeneration begins with the external man and moves on to the internal. This is why there is a different order here, with external things coming first.