Explanation: The scratches up in the corner are a mocking caricature of a crucified man - part of the Alexamenos graffito, which made fun of that newfangled religion called "Christianity". Glad that weird death-cult stuff worshipping a condemned criminal never caught on!
The Latin text reads "Barbarians" at the top, and "Is this the son of God?" at the bottom, in the vein of the classic "Is this a pigeon?" meme of some anime guy gesturing at a butterfly.