21It is written in the Law:
“By strange tongues and foreign lips
I will speak to this people,
but even then they will not listen to Me,
says the Lord.”
22Tongues, then, are a sign, not for believers, but for unbelievers. Prophecy, however, is for believers, not for unbelievers.
23So if the whole church comes together and everyone speaks in tongues, and some who are uninstructed or some unbelievers come in, will they not say that you are out of your minds?
— 1 Corinthians 14:21-23