1st Corinthians 14:27

24 and if all may prophecy, and any one may come in, an unbeliever or unlearned, he is convicted by all, he is discerned by all,

25 and so the secrets of his heart become manifest, and so having fallen upon [his] face, he will bow before God, declaring that God really is among you.

26 What then is it, brethren? whenever ye may come together, each of you hath a psalm, hath a teaching, hath a tongue, hath a revelation, hath an interpretation? let all things be for building up;

27 if an [unknown] tongue any one do speak, by two, or at the most, by three, and in turn, and let one interpret;

28 and if there may be no interpreter, let him be silent in an assembly, and to himself let him speak, and to God.

29 And prophets -- let two or three speak, and let the others discern,

30 and if to another sitting [anything] may be revealed, let the first be silent;