17. For you may very well be giving thanks, but the other person is not being built up.
18. I thank God that I speak in other languages more than all of you;
19. yet in the church I would rather speak five words with my understanding, in order to teach others also, than 10,000 words in another language.
20. Brothers, don’t be childish in your thinking, but be infants in regard to evil and adult in your thinking.
21. It is written in the law:I will speak to these peopleby people of other languagesand by the lips of foreigners,and even then, they will not listen to Me, says the Lord.
22. It follows that speaking in other languages is intended as a sign, not for believers but for unbelievers. But prophecy is not for unbelievers but for believers.