Fish represent knowledge. Fish laid upon the fire, as in John 21:9, represent the reformation of the natural man by the good of love, of which description were all the men of that time, in consequence of the complete vastation of the church. Fish signify sensual affections which are the ultimate affections of the natural man. Fish sometimes also represent people in common truth or conversely in external falsity. Broiled fish, as in Luke 24:42, signify the truth of good relating to the natural and sensual man, and honeycomb, the good of the same truth. To make as the fishes of the sea, signifies to make altogether sensual. Fish, as in Habakkuk 1:14-16, signify people in faith separate from charity.

(References: Apocalypse Revealed 405; Luke 24)

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)