1 Corinthians 14:22-24

Worsley(i) 22 So that tongues are for a sign, not to believers but to unbelievers: but prophecy not to unbelievers but to those that believe. 23 If then the whole church be come together and all speak in unknown tongues, and there come in illiterate persons, or infidels, will they not say that ye are mad? 24 But if all prophesy, and there come in an unbeliever, or one unlearned, he is convinced by all, he is judged by all.