8. For example, if the trumpet made an uncertain sound, who would prepare himself for battle?
9. So it is with you also, for unless you utter with the tongue in plain speech, how will it be known what is said? For then you would be speaking into the air.
10. Consider that there are so many different kinds of languages in this world, and yet none is without a voice.
11. Therefore, if I do not understand the nature of the voice, then I shall be like a foreigner to the one with whom I am speaking; and he who is speaking will be like a foreigner to me.
12. So it is with you also. And since you are zealous for what is spiritual, seek the edification of the Church, so that you may abound.
13. For this reason, too, whoever speaks in tongues, let him pray for the interpretation.
14. So, if I pray in tongues, my spirit prays, but my mind is without fruit.
15. What is next? I should pray with the spirit, and also pray with the mind. I should sing psalms with the spirit, and also recite psalms with the mind.
16. Otherwise, if you have blessed only with the spirit, how can someone, in a state of ignorance, add an "Amen" to your blessing? For he does not know what you are saying.