The ‘hidden things’ are therefore mysteries — but only so, to the foreign spirits of others who may be listening. For none of the language-speaker’s listeners — nobody (oudeis) –then understands him. Nobody — unless his tongue-speakings are translated, for the listeners’ benefit!
Quite different to such untranslated public language-speakings, however, are ‘prophecies’ or forthtellings of God’s Word –whether spoken directly into the Corinthian dialect, or whether translated thereinto from some other language. On the character of prophecy, see my other article Revival Through Prophesying (Brisbane, 1990). Here, however, we would only establish that even untranslated language-speaking was very edifying to — and therefore thoroughly understood by — the language-speaker himself!