1 Corinthians 14:9-11

WPNT(i) 9 So it is with you: if you do not deliver an intelligible message with the ‘language’, how will it be known what is being said? You will just be speaking into the air. 10 There are probably a great many kinds of sounds in the world, and none of them is without significance. 11 But if I don’t know the force of the sound, I will be a foreigner to the speaker, and he will be a foreigner to me.