1 Corinthians 14:7-11

Similarly, if musical instruments, such as flutes or stringed instruments, are out of tune and don’t play the arrangement clearly, how will anyone recognize the melody? If the bugle makes a garbled sound, who will recognize the signal to show up for the battle? So it is with you. Unless you speak in a language that’s easily understood, how will anyone know what you’re talking about? You might as well save your breath! I suppose that the world has all sorts of languages, and each conveys meaning to the ones who speak it. But I am like a foreigner if I don’t understand the language, and the speaker will be like a foreigner to me.