1 Corinthians 14:6-12 

⁶ So now, brothers and sisters, if I come to you speaking in tongues, how will I benefit you unless I speak to you with a revelation or knowledge or prophecy or teaching? ⁷ Even lifeless instruments that produce sounds—whether flute or harp—if they don’t make a distinction in the notes, how will what is played on the flute or harp be recognized? ⁸ In fact, if the bugle makes an unclear sound, who will prepare for battle? ⁹ In the same way, unless you use your tongue for intelligible speech, how will what is spoken be known? For you will be speaking into the air. ¹⁰ There are doubtless many different kinds of languages in the world, none is without meaning. ¹¹ Therefore, if I do not know the meaning of the language, I will be a foreigner to the speaker, and the speaker will be a foreigner to me. ¹² So also you—since you are zealous for spiritual gifts, seek to excel in building up the church.