Large bodies of water often symbolize the unconscious, so any sea creature can represent a message from the unconscious or “diving” into the unconscious. Completely at home in the ocean, fish are the best-equipped creatures for exploring its depths, and are thus positive symbols for anyone engaged in therapy or self transformation.
The activity of fishing can indicate a quest, particularly for nourishment, and it can indicate an exploration of the unconscious. Fish can also be sexual symbols and, because of their association with Christianity, can be Christ symbols.
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