What does 1 Corinthians 14:24 mean?
In the previous verse, Paul imagined an unbeliever entering into a Christian church service in which everyone is speaking in tongues, with nobody to interpret what is being said. The inevitable conclusion of these unbelievers would be that Christians were out of their minds, a group of crazy people. Even if those Christians were speaking words given by God in a real language, the lack of an interpreter would ensure that nobody would perceive any truth.Now Paul contrasts that with a slightly different scenario: an unbeliever arriving as everyone is exercising the gift of prophecy. This gift was thought to be the Holy Spirit-empowered ability to clearly declare God's specially revealed truth for the benefit of others.
The result in this scenario would be exactly the opposite of an unbeliever witnessing an uncontrolled use of the tongues gift. Those hearing God's Word as legitimately delivered to them through the gift of prophecy would experience conviction. They would be able to understand and process what they heard. They could become aware of and burdened by their own guilt for their sinfulness. They would be forced to be accountable for their sin and for their response to God's offer of grace through faith in Christ.
It's important to understand that not everyone in the church at Corinth had the gift of tongues or the gift of prophecy. Paul has written that they should desire that some have the gift of prophecy (1 Corinthians 14:1), and he has even said he wishes all of them had the gift of tongues (1 Corinthians 14:5). Only a portion of them had either gift, however.
Paul's point is that if everyone could prophesy, it would be far better for unbelievers than if everyone could speak in tongues.