Paul continued his argument by clarifying the effect that unintelligible speech has on believers gathered for worship.
14:13 The Corinthian who already had the gift of tongues should ask the Lord for the ability to interpret his or her utterances so the whole church could benefit from them (cf. v. 5). Note that Paul never said they should abandon this gift, but their practice of it needed correcting.
14:14 Public prayer is in view here, as it is in this whole chapter (v. 16), but some may have been praying in tongues privately as well. While praying in a tongue might give the person doing so a certain sense of exultation in his spirit, his mind would not benefit. He would not know what he was saying. The "spirit"(Gr. pneuma) seems to refer to that part of the person that exercises this spiritual gift. It is separate from the mind obviously (cf. v. 4). The person's spirit prays as the Holy Spirit gives him or her utterance.
14:15 Paul advocated praising and praying to God with both the spirit (emotions) and the mind (understanding).329One reason tongues is an inferior gift is that in it the reason has no control.
Sometimes modern Christians who believe they have the gift of tongues wonder if they should speak in tongues in private even though they do not know what they are saying. Some of them claim that doing so edifies them (v. 4). Let us assume they are speaking some language that they have not studied, which is what the tongues-speakers in the early church were speaking. This, by the way, eliminates most modern tongues-speakers since most modern tongues-speakers simply repeat gibberish.330Paul did not discourage speaking unknown languages in private. Nonetheless the relative value and profitability of such an experience are so minimal that its practice seems almost foolish in view of the more edifying options that are open to Christians. Perhaps the current preoccupation with feeling good, in contrast to having to work hard with one's mind to edify the church, is what make this practice so attractive to many today.
"It is, of course, impossible for anyone to prove experimentally that speaking in tongues cannot occur today. It may be demonstrated, however, that speaking in tongues is not essential to God's purpose now, and that there are good reasons to believe that most if not all the phenomena which are advanced as proof of modern speaking in tongues is either psychological or demonic activity."331
14:16-17 Paul used the word "bless"for pray here. When we praise God in prayer we say a benediction on Him, a word of blessing. Those believers (Gr. idiotes) who do not understand what the person praying in tongues is saying are unable to add their affirmation at the end of the prayer. "Amen"means "so be it."Whenever we lead in public prayer we should do it so the other people praying can join us and affirm our words. It is clear in verse 16 that Paul was speaking about a public worship situation. Giving thanks in public worship is important even if no one else joins in, but it is even more important that other believers can join in.
14:18-19 Corinthian tongues-enthusiasts could not reject Paul's instruction because he did not have the gift himself and so failed to appreciate its value. He believed in the validity of the gift but did not value it highly.332He almost deprecated it. Edifying instruction was 10,000 times more important than personal private exultation for the building up of the church gathered for worship. The edification of the body is, of course, God's great purpose for Christians today (Matt. 16:18).
Paul affirmed the gift that the Corinthians apparently regarded as the sign of genuine spirituality, but he did so by correcting their thinking about what was really important in their meetings. Worship should never be selfish, but it should always be intelligible.333
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