1 Cor 14:6-11
6* Now, brothers, if I should come to you speaking in tongues, what good will I do you if I do not speak to you by way of revelation, or knowledge, or prophecy, or instruction? 7Likewise, if inanimate things that produce sound, such as flute or harp, do not give out the tones distinctly, how will what is being played on flute or harp be recognized? 8And if the bugle gives an indistinct sound, who will get ready for battle? 9Similarly, if you, because of speaking in tongues, do not utter intelligible speech, how will anyone know what is being said? For you will be talking to the air. 10It happens that there are many different languages in the world, and none is meaningless; 11but if I do not know the meaning of a language, I shall be a foreigner to one who speaks it, and one who speaks it a foreigner to me.