1 Corinthians 14:20-25

20Brethren, be not children in [your] minds, but in malice be babes; but in [your] minds be grown [men].

21It is written in the law, By people of other tongues, and by strange lips, will I speak to this people; and neither thus will they hear me, saith the Lord.

22So that tongues are for a sign, not to those who believe, but to unbelievers; but prophecy, not to unbelievers, but to those who believe.

23If therefore the whole assembly come together in one place, and all speak with tongues, and simple [persons] enter in, or unbelievers, will not they say ye are mad?

24But if all prophesy, and some unbeliever or simple [person] come in, he is convicted of all, he is judged of all;

25the secrets of his heart are manifested; and thus, falling upon [his] face, he will do homage to 1God, reporting that 2God is indeed amongst you.