1 Corinthians 14:20-23
14:20 Brothers and sisters, do not be children in your thinking. Instead, be infants in evil, but in your thinking be mature.
14:21 It is written in the law: “By people with strange tongues and by the lips of strangers I will speak to this people, yet not even in this way will they listen to me,” says the Lord.
14:22 So then, tongues are a sign not for believers but for unbelievers. Prophecy, however, is not for unbelievers but for believers.
14:23 So if the whole church comes together and all speak in tongues, and unbelievers or uninformed people enter, will they not say that you have lost your minds?