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.

(Riferimenti: Apocalypse Revealed 405; Luke 24)

404. And a third of the sea became blood. This symbolically means that general truths had all been falsified in them.

A third means, symbolically, all (no. 400). Blood symbolizes the falsification of the Word's truth (no. 379). The sea symbolizes the church in people concerned with its external elements and caught up in faith alone (nos. 398, 402). General truths are falsified among such people because they are concerned with those truths alone, as they do not know the particulars of that faith, as the clergy do. It is because of those general truths in them that they appear in the spiritual world to be at sea. That is because waters symbolize truths (no. 50), and the sea is the general receptacle of them (no. 238).