Meta. Ideas of multiplication, fecundity.
The reason why Jesus so often used fish to illustrate His teaching was that He was a living demonstration of ideas, and all that He did was in the realm of ideas rather than the realm of effects. Fish represent ideas in which there is great possibility of increase; Jesus used these ideas to represent the inexhaustible, everywhere present abundance.
Like all Scripture, the passage that tells of Jesus' eating fish should be read in the spirit and not in the letter. Jesus came to establish the reign of righteousness and to bring about the time when "they shall not hurt nor destroy in all my holy mountain." Therefore we must look back of the mere letter and find the spiritual significance of every act of His. There is evidence that the accounts in which Jesus figures as a party to fish eating are symbolical of the mental side of eating, which is the appropriation of ideas, fish representing ideas.