The word cista was generally used to signify any square or cylindrical box or basket of wicker, woven wood, or metal, which might be used to hold food, money (more usually an arca), jewelry, toiletries, or books (though the more precise term for a book box was capsa); the same word was used for the ballot box. The cista mystica was used to hold sacred religious items, especially in the Eleusinian rites.

Without question Umbricius is not speaking of a container as artistic and elegant as the above bronze jewel casket from Praeneste, inscribed with scenes from the voyage of the Argonauts; the box holding the poor tenant's Greek books is vetus and may in its earlier days have served more mundane purposes.