1 Corinthians 14:20-25
20 “Brothers and sisters, do not be children in your thinking; yet in evil be infants, but in your thinking be mature. 21 In the [i]Law it is written: “By men of strange tongues and by the lips of strangers I will speak to this people, and even so they will not listen to Me,” says the Lord. 22 So then, tongues are for a sign, not to those who believe but to unbelievers; but prophecy is not for unbelievers, but for those who believe. 23 Therefore if the whole church gathers together and all the people speak in tongues, and [j]outsiders or unbelievers enter, will they not say that you are insane?24 But if all prophesy, and an unbeliever or an [k]outsider enters, he is convicted by all, he is called to account by all; 25 the secrets of his heart are disclosed; and so he will fall on his face and worship God, declaring that God is certainly among you.”
Paul is not speaking of angels coming down and talking to people but rather strangers from other nations that come speaking in strange tongues. This concept is seen at Pentecost in Acts 2. This is why Paul views tongues as a gift for unbelievers. Unbelievers and foreigners hear the Gospel in their own language and believe in Jesus. This is why tongues is to be used outside of the church for unbelievers.
All people speak in tongues: To bring tongues into the church service is to create mass confusion for anyone coming into the gathering. Instead, the gift is meant to be evangelistic for unbelievers. This is contrasted to prophecy which edifies all people and consequently ought to be present within the church service.
