1 Corinthians 14:21-25

21In the Law it is written: “With other tongues and through the lips of foreigners I will speak to this people, but even then they will not listen to me, says the Lord.” Isaiah 28:11,12 22Tongues, then, are a sign, not for believers but for unbelievers; prophecy, however, is not for unbelievers but for believers. 23So if the whole church comes together and everyone speaks in tongues, and inquirers or unbelievers come in, will they not say that you are out of your mind? 24But if an unbeliever or an inquirer comes in while everyone is prophesying, they are convicted of sin and are brought under judgment by all,

25as the secrets of their hearts are laid bare. So they will fall down and worship God, exclaiming, “God is really among you!”