This engraved fish might refer to the Christian symbol of the ichthys, one of the oldest Christian symbols to have come down to us. It was presumably used as a sign of recognition amongst Christians. The letters of the word fish in ancient Greek are written in capital letters (ΙΧΘΥΣ). These letters form an acronym with the initials of the expression ‘Ἰησοῦς Χριστός, Θεοῦ ͑Υιός, Σωτήρ’, which means ‘Jesus Christ, Son of God, Saviour’.
In addition, the symbol of the fish was associated with the Greek god, Orpheus, who was described as a “fisher of men”. The descent of Orpheus into the underworld to save the soul of his lover, Eurydice, also became a metaphor for Christ the Saviour. The fish decorating this fragment may have had Christian significance, but it is equally likely that it was strictly a decorative motif.
In Ancient Rome the fish could have many meanings and uses. In the Defense of Apuleius the writer has to defend himself against charges of magic and witchcraft due to the fact a certain type of fish was found in his house! Fish were also very important to the mediterranean diet as Fish Sauce was a key flavouring in the Ancient World.
For more information about the meanings of animals in Roman art, see our relevant blog post: Animal Symbolism in Roman Art.