This tattoo belongs to Mirabai Knight:
This is my Latin palindrome tattoo. It's not from any specific literary work; it's actually a piece of graffiti dating back at least 2,000 years. It's been found inscribed on walls and stones in cities all over Europe, from Herculaneum to Manchester. It literally translates to "The sower Arepo holds the wheels at work", and might have its origins in the worship of Mithras, Persian god of the sun, though not much is conclusively known. It's the only sentence in any language that can be arranged in a grid to read identically in four different directions.
You can read more about the Sator Square on Wikipedia.