Parallel
1 Corinthians 14:11
Clementine Vulgate · Berean Standard Bible
Si ergo nesciero virtutem vocis, ero ei, cui loquor, barbarus : et qui loquitur, mihi barbarus.
If, then, I do not know the meaning of someone’s language, I am a foreigner (note: Literally a barbarian; twice in this verse) to the speaker, and he is a foreigner to me.