1 Corinthians 14:9-11

Complete Jewish Bible

⁹ It’s the same with you: how will anyone know what you are saying unless you use your tongue to produce intelligible speech? You will be talking to the air! ¹⁰ There are undoubtedly all kinds of sounds in the world, and none is altogether meaningless; ¹¹ but if I don’t know what a person’s sounds mean, I will be a foreigner to the speaker and the speaker will be a foreigner to me.