512. And the third part of the sea became blood, signifies that in consequence everything therein became the falsity of evil. This is evident from the signification of the "third part," as being all (See above, n. 506); also from the signification of the "sea," as being the natural man (See just above, n. 511); therefore "the third part of the sea" signifies the whole natural man and everything therein; also from the signification of "blood," as being falsity of evil (See also above, n. 329). From this the spiritual sense of this verse can be seen, namely, that "the great mountain burning with fire was cast into the sea, and the third part of the sea became blood," signifies that the love of self, when it enters into and occupies the natural man, turns every knowledge [scientificum] into the falsity of evil.

[2] The love of self is a love purely corporeal, springing from the rising up and fermenting of worn out parts and the titillation caused by these inwardly in the body; in consequence of which the perceptive faculty of the mind, which requires a pure atmosphere, not only becomes dull and gross, but even perishes. That this is the origin of the love of self can be seen from its correspondence with human dung; for those who have been corroded by this love, when they come into the other life love above all things stercoraceous filth, and its stench is grateful to them, which proves that the effluvium therefrom pleasantly affects the sensory of their smell, as it had before affected the general sensory, which is extended by interior cuticles in every direction. From this alone it can be seen that the love of self is more gross and foully corporeal than any other love, and consequently that it takes away all spiritual perception, which is a perception of the truth and good of heaven and the church. Moreover, it shuts up the spiritual mind and fixes its seat entirely in the natural and sensual man, which communicates most closely with the body and has no communication with heaven. From this again it comes to pass that all those in whom the love of self is dominant are sensual, and do not see the things that belong to heaven and the church except in the densest darkness; and furthermore they reject and deny these whenever they are alone and are thinking with themselves. From this the signification of "the third part of the sea became blood, in consequence of the great mountain burning with fire that was cast into it," can now be seen.

511. Was cast into the sea, signifies into the natural man. This is evident from the signification of the "sea," as being the knowledge [scientificum] in general which is in the natural man, consequently the natural man in respect to its knowledge there (See above n. 270, 342). This is the signification of "sea," because "water" signifies truth, and truth in the natural man is called knowledge [scientificum]; but truth itself is in itself spiritual, and in the spiritual man makes one with the affection of truth, for it is a form of affection there; consequently so far as this affection with its form is therefrom in the knowledges that are in the natural man, so far the knowledges contain in themselves truths, and are true knowledges; for the knowledges of the natural man, viewed in themselves, are not truths, but only containing vessels of truth, therefore "vessels" in the Word signify knowledges.

[2] That the "sea" signifies the natural man can be seen from passages in the Word cited above (n. 275, 342, which makes clear that the "sea" in reference to its water signifies knowledge [scientificum] in general, while the "sea" in reference to its waves signifies disputation and reasoning, which are maintained by knowledges; and as both knowledges and reasoning are in the natural man, therefore the "sea" signifies the natural man itself. But the state of the natural man is wholly in accordance with the affection of man's love. When spiritual affection, that is, affection of good and truth for the sake of good and truth, is dominant in man, and when this affection flows in through the spiritual into the natural man, then the natural man is a spiritual-natural man, for it is subordinate and subject to the spiritual, and as they thus act as a one, both are in heaven. But so long as a merely natural affection is dominant in man, there is in the natural man no truth, but everything therein is knowledge [scientificum] not true, it is dead knowledge and false knowledge, for the reason that the knowledges therein then conjoin themselves with affections merely natural, all of which spring from the loves of self and of the world, while truths themselves, because in themselves they are spiritual, conjoin themselves only with spiritual affections, as has been said above. When truths conjoin themselves with affections merely natural, they are no longer truths but falsities, for affection merely natural falsifies truths. Conjunctions of truth with affections merely natural correspond to whoredoms and adulteries of various kinds, and in the spiritual sense are meant in the Word by various kinds of whoredoms and adulteries. There are conjunctions of the truths of the Word with the love of self and the world that correspond to these.

[3] That the "sea" signifies the natural man with the things that are in it is also from correspondence; for in the spiritual world seas appear in various places, especially about the outmost boundaries where spiritual societies or heaven itself ends. There are seas there because in the boundaries of heaven and beyond them those dwell who have been merely natural men, and these appear there in deep places, where they have their abodes; the natural men there, however, are not evil, but the evil natural men are in the hells. The seas there seen also make evident what those are who are in them, especially from the color of the waters, as verging towards darkness or clearness; if towards darkness those therein are sensual spirits, who are the lowest natural, and if towards clearness those therein are the interior natural. But the waters of the seas that are over the hells are dense, black, and sometimes ruddy; and the infernal crew therein appear like snakes and serpents, and like such monsters as are in seas.