1 Corinthians 14:9-11 Evangelical Heritage Version (EHV)
9 So also with you: Unless you use your tongue to produce intelligible speech, how will anyone know what is being spoken? To be sure, you will be speaking only into the air.
10 There are perhaps ever so many kinds of languages in the world, and not one of them is without meaning. 11 Accordingly, if I do not understand the language, I will be a foreigner to the speaker, and he will be a foreigner to me.