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.
17. In this case, certainly, you give thanks well, but the other person is not edified.
18. I thank my God that I speak in tongues for all of you.
19. But in the Church, I prefer to speak five words from my mind, so that I may instruct others also, rather than ten thousand words in tongues.
20. Brothers, do not choose to have the minds of children. Instead, be free of malice like infants, but be mature in your minds.
21. It is written in the law: "I will speak to this people with other tongues and other lips, and even so, they will not heed me, says the Lord."
22. And so, tongues are a sign, not for believers, but for unbelievers; and prophecies are not for unbelievers, but for believers.
23. If then, the entire Church were to gather together as one, and if all were to speak in tongues, and then ignorant or unbelieving persons were to enter, would they not say that you were insane?