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.

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

9621. 'And you shall join five curtains together by themselves, and six curtains by themselves' means unceasing communication of truth with good and of good with truth, as above in 9604.