1 Corinthians 14:22
Tongues, then, are a sign, not for believers, but for unbelievers. Prophecy, however, is for believers, not for unbelievers.
Berean Standard Bible
Wherefore tongues are for a sign, not to them that believe, but to them that believe not: but prophesying serveth not for them that believe not, but for them which believe.
Therefore other languages are for a sign, not to those who believe, but to the unbelieving; but prophesying is for a sign, not to the unbelieving, but to those who believe.