1 Corinthians 14:9-11

World English Bible

⁹ So also you, unless you uttered by the tongue words easy to understand, how would it be known what is spoken? For you would be speaking into the air. ¹⁰ There are, it may be, so many kinds of languages in the world, and none of them is without meaning. ¹¹ If then I don’t know the meaning of the language, I would be to him who speaks a foreigner, and he who speaks would be a foreigner to me.