The Commodilla catacomb inscription is found on the cornice of a fresco in the tomb of the Christian martyrs Felix and Adauctus, located in the catacombs of Commodilla in Rome.[1] The graffito has an important place in the history of Italian, as it represents a form of language intermediate between Latin and Old Italian.
The inscription is spread over six lines:This may be divided into words as non dicere ille secrita a bboce ('don't say the secrets aloud'), referring to Christian mysteria or secret prayers to be recited under one's breath.[2]
The inscription has to post-date the fresco on which it is written, which can itself be dated to the 6th or 7th century on stylistic grounds (thus establishing the terminus post quem). The terminus ante quem can be estimated on the following grounds:
Altogether these point to a date around the beginning of the 9th century.
The language used is a sort of late 'Vulgar Latin', more archaic than Old Italian and closer to Latin. The word Romance languages: ille, from Latin Latin: illae or Latin: illās ("those", feminine plural), does not conserve its original demonstrative meaning but is used as a feminine plural definite article instead.
In the word Romance languages: secrita, ⟨i⟩ is used to represent [e] (and not pronounced as /[i]/), as was common practice in the pre-Carolingian writing of Italy and elsewhere.[3]
The spelling Romance languages: bboce is of special interest. At first the word had been written Romance languages: boce, but afterwards, either the same writer or another felt that the spelling did not reflect his pronunciation closely enough, and so he inserted an additional ⟨b⟩ in superscript. This hints at the pronunciation of the Roman dialect at the time, characterized on the one hand by syntactic doubling (still typical in the area today) and on the other hand by betacism or the merger of Latin /b/ and /w/ (thus Latin Latin: ad vōcem resulted in Romance languages: a bboce).