Summary of my views
The speaking in tongues as practiced by charismatics is not a language any more than a baby crying is a language. There is no vocabulary, no grammar, no syntax, no communication of ideas.
Although the early Christians probably copied this practice of speaking in tongues from the pagans, Paul does not strictly forbid its use (but he does drastically restrict its use).
The Biblical form of speaking in tongues is when someone speaks in a language they do not know but that the listeners around them do know. That Paul speaks in tongues more than any of them is not surprising since he was a miracle worker.
Prophecy vs. Tongues
In this entire first section Paul emphasizes the use of prophecy and criticizes the use of tongues.
(1 Corinthians 14:1) Follow after charity, and desire spiritual gifts, but rather that ye may prophesy.
Paul emphasizes love and prophecy. He excludes tongues.
(1 Corinthians 14:2) For he that speaketh in an unknown tongue speaketh not unto men, but unto God: for no man understandeth him; howbeit in the spirit he speaketh mysteries.
We should not speak to someone in a language they don't understand because the purpose of language is to communicate ideas.
Speaking in tongues does not help other people in the slightest, it is a solo activity. As such it has no place in the church service.
(1 Corinthians 14:3) But he that prophesieth speaketh unto men to edification, and exhortation, and comfort.
In contrast to tongues, prophecy has value to others.
(1 Corinthians 14:4) He that speaketh in an unknown tongue edifieth himself; but he that prophesieth edifieth the church.
Speaking in tongues has no benefit to anybody.
(1 Corinthians 14:5) I would that ye all spake with tongues, but rather that ye prophesied: for greater is he that prophesieth than he that speaketh with tongues, except he interpret, that the church may receive edifying.
In this verse I believe Paul is referring to speaking another language that people can understand. If someone speaks in this kind of tongues then there also needs to be an interpreter so everyone can understand. I think Paul is mocking them by suggesting they should have interpreters when they know full well they are not speaking an intelligible language — no one could possibly interpret because they are speaking gibberish.
(1 Corinthians 14:6) Now, brethren, if I come unto you speaking with tongues, what shall I profit you, except I shall speak to you either by revelation, or by knowledge, or by prophesying, or by doctrine?
Paul reminds them he speaks to them in a language they understand.
(1 Corinthians 14:7) And even things without life giving sound, whether pipe or harp, except they give a distinction in the sounds, how shall it be known what is piped or harped?
Even musical instruments have to have clear tones and need to sound musical to be useful. Mere noise is useless; it is certainly not art nor worship.
(1 Corinthians 14:8) For if the trumpet give an uncertain sound, who shall prepare himself to the battle?
For a trumpet to signal the troops it has to have clear tones and form a recognizable pattern. The tongues that are being spoken in the Corinthian church have neither — it is mere gibberish.
(1 Corinthians 14:9) So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air.
The purpose of speech is communicating ideas.
(1 Corinthians 14:10) There are, it may be, so many kinds of voices in the world, and none of them is without signification.
(1 Corinthians 14:11) Therefore if I know not the meaning of the voice, I shall be unto him that speaketh a barbarian, and he that speaketh shall be a barbarian unto me.
Speaking languages (or non-languages) uncomprehensible to others does not unite people.
(1 Corinthians 14:12) Even so ye, forasmuch as ye are zealous of spiritual gifts, seek that ye may excel to the edifying of the church.
Especially in church our use of spiritual gifts should edify one another. Tongues do not do this.
I think Paul is mocking the Corinthians by telling them they need to interpret these tongues. Of course they can't do it because it is not really a language.
(1 Corinthians 14:13) Wherefore let him that speaketh in an unknown tongue pray that he may interpret.
If someone miraculously speaks a real foreign language (presumably that someone else within hearing range understands), they should also seek to miraculously interpret so that others can also understand what was said.
(1 Corinthians 14:14) For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.
The question is whether Paul thinks our spirit can pray without our being aware of it or without our being aware of the content or meaning of the prayer.
The phrase "unknown tongue" seems to refer to words that have no meaning to the listeners, whether it is a real foreign language or a nonsense language that is not really a language at all. Paul uses this phrase many times in this chapter.
(1 Corinthians 14:15) What is it then? I will pray with the spirit, and I will pray with the understanding also: I will sing with the spirit, and I will sing with the understanding also.
Paul expects us to pray in an understandable manner. In other words, we need to know the content of what we are praying about. Prayer is not merely going through the motions of doing or saying things having no meaning.
(1 Corinthians 14:16) Else when thou shalt bless with the spirit, how shall he that occupieth the room of the unlearned say Amen at thy giving of thanks, seeing he understandeth not what thou sayest?
The phrase "bless with the spirit" seems to indicate speaking understandable words; perhaps to bless God; perhaps to bless others. In any case, Paul emphasizes that these kinds of utterances must be understandable to all, especially to those who are either not yet Christians or who are still learning the faith.
(1 Corinthians 14:17) For thou verily givest thanks well, but the other is not edified.
The phrase "giving thanks" seems to mean the same things as "bless with the spirit." Paul mentions again the importance of other people understanding the meaning of the utterances so they can be blessed by them.
(1 Corinthians 14:18) I thank my God, I speak with tongues more than ye all:
In this verse Paul is referring to his activities outside of the church (see verse 19).
Paul speaks in tongues more than anyone else. After mentioning the importance of people being able to understand these utterances, why would Paul brag that he speaks gibberish? He wouldn't of course. When Paul speaks in tongues he certainly speaks a language understood by those around him. In my opinion, he is referring to speaking the language of the people, either languages he knows or, perhaps, miraculously through the power of the Holy Spirit, languages he doesn't know (as the apostles did in Acts 2:6).
(1 Corinthians 14:19) Yet in the church I had rather speak five words with my understanding, that by my voice I might teach others also, than ten thousand words in an unknown tongue.
Paul contrasts his speaking in tongues outside of church (verse 18) with his speaking in church (verse 19). In verse 19 he clearly states he doesn't want to speak in tongues at all and he seems to assume other Christians should have the same opinion about this as he does.
Even if verse 18 refers to Paul's speaking gibberish (in private) more than anyone else does, in verse 19 he clearly states this is not proper in church. Yet many charismatic Christians include speaking in tongues as part of their service.
Paul repeatedly highlights the importance of speaking words understandable to others. That point seems to be what he wants his readers of this letter to take away from this chapter.
(1 Corinthians 14:20) Brethren, be not children in understanding: howbeit in malice be ye children, but in understanding be men.
(1 Corinthians 14:21) In the law it is written, With men of other tongues and other lips will I speak unto this people; and yet for all that will they not hear me, saith the Lord.
The reason I think Paul in verse 18 is referring to speaking other languages understandable to his audience is his reference to Isaiah 28:11. The Babylonians who took the Israelites away into captivity spoke another language which was not understandable to the Israelites. This act was a judgment on them for not being true to God's law. They should have noticed that this judgment was because of their disobedience but they failed to understand the message even though Isaiah and the other prophets told them ahead of time what was happening.
(1 Corinthians 14:22) 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.
Referring to Isaiah 28:11: the language of the Babylonians who carried the Israelites to captivity were a sign for those who didn't believe Isaiah's warnings, who wouldn't turn back to God. The words of the prophet Isaiah were believed by some.
This verse contrasts two kinds of words, two kinds of people, and two kinds of outcomes:
The faithful Israelites were also taken away into captivity by the Babylonians, but for them it was not in judgment of their sins but, rather, for the sins of their fellow countrymen. It is hard to see how Isaiah's warnings could possibly have served these faithful Israelites except that it would have encourged them to continue being faithful to God rather than fall into sin with their fellow countrymen. Being reminded God hates sin is always a good thing for those who wish to please God.
Paul is concerned for the unbelievers who are attending the church service. When everyone is speaking in tongues these unbelievers are not edified in the slightest; they do not hear the gospel message of salvation. One purpose of prophecy is to evangelize to these unbelievers.
(1 Corinthians 14:23) If therefore the whole church be come together into one place, and all speak with tongues, and there come in those that are unlearned, or unbelievers, will they not say that ye are mad?
Paul is concerned with the effects on unbelievers and those who are still learning about Christianity. He seems to think the church service should not offend them or confuse them. I would think it would be okay if certain parts of a church service were mysterious to these people, but Paul seems to think otherwise. Perhaps this is because the majority of the church service of the Corinthians was chaotic and confusing.
(1 Corinthians 14:24) But if all prophesy, and there come in one that believeth not, or one unlearned, he is convinced of all, he is judged of all:
I doubt if Paul is suggesting the Corinthians merely exchange their chaotic tongues-speaking with chaotic prophesying. I suspect he is comparing the effect on these unbelievers or unlearned with hearing gibberish versus hearing clear teaching in a language they understand.
(1 Corinthians 14:25) And thus are the secrets of his heart made manifest; and so falling down on his face he will worship God, and report that God is in you of a truth.
Speaking tongues not understandable by others does nothing to convince people of the truthfulness and trustworthiness of the message. People can only judge the value of a proposition if they understand it. Gibberish just confuses people and frustrates them. It has no place in a church service.
Order / Radically restricting the use of Charismatic gifts
The church service is to be orderly. Paul puts severe restrictions on the use of tongues and prophecy in the church service. Many charismatic denominations ignore Paul's commands.
(1 Corinthians 14:26) How is it then, brethren? when ye come together, every one of you hath a psalm, hath a doctrine, hath a tongue, hath a revelation, hath an interpretation. Let all things be done unto edifying.
If Paul is speaking to the congregation at large then it sounds like most everyone is very gifted and participates in the church service. This church is more like an interactive home fellowship than a church. Perhaps Paul is referring to merely those people who do lead the church service, perhaps a dozen people or so.
(1 Corinthians 14:27) If any man speak in an unknown tongue, let it be by two, or at the most by three, and that by course; and let one interpret.
This is a severe restriction on their activities during the church service. If they followed Paul's command the church services would have changed drastically. But they probably ignored him.
(1 Corinthians 14:28) But if there be no interpreter, let him keep silence in the church; and let him speak to himself, and to God.
Charismatics often claim the utterances (babblings) of those speaking in tongues can be interpreted. But how can something which is not a language at all be interpreted? This idea is nonsense. I think it is more likely Paul is referring to people speaking in another language understood by some in the congregation. These utterances should be interpreted so the rest of the people can understand also.
(1 Corinthians 14:29) Let the prophets speak two or three, and let the other judge.
Paul commands them to restrict their prophetic utterances by the congregation at large to 2 or 3. This surely would drastically change the character of the church service. I suspect all these prophets were not too happy about this. I also suspect they ignored Paul's commands.
(1 Corinthians 14:30) If any thing be revealed to another that sitteth by, let the first hold his peace.
Charismatics seem to think every time the Holy Spirit plants a thought in their head they must speak it out for everyone to hear. But here we have an example of the Holy Spirit planting the same thought in several people's heads. Paul mentions only one of them needs to speak it out.
Perhaps the mechanism by which divinely-inspired thoughts are planted in our heads needs some examination. Rather than the idea that the Holy Spirit singles-out people to receive a message; perhaps we should consider that all human souls live in the spiritual realm and receive divine messages all the time — after all, God lives in the spiritual realm and is fully capable of being heard above the noise and chaos of the demonic and satanic influences. Perhaps the souls of many people often hear the same messages at the same time because their souls are located in the same general spiritual place where the message is being delivered by God through an angel. Only a few people actually notice these messages implanted in their souls in the spiritual realm. No one is under any obligation to share every message their soul receives in the spiritual realm.
(1 Corinthians 14:31) For ye may all prophesy one by one, that all may learn, and all may be comforted.
I'm surprised they had to be told to prophecy one at a time. The church service must have been pandemonium, a lot like some charismatic churches of today that ignore Paul's commands.
(1 Corinthians 14:32) And the spirits of the prophets are subject to the prophets.
Prophets are to control the use of their gifts. They must decide when and if to proclaim their prophetic utterances.
(1 Corinthians 14:33) For God is not the author of confusion, but of peace, as in all churches of the saints.
I believe Paul is accusing the Corinthians of having confusing, disorderly services. Charismatics who use this chapter to support their views don't seem to be understanding what Paul is really saying.
(1 Corinthians 14:34) Let your women keep silence in the churches: for it is not permitted unto them to speak; but they are commanded to be under obedience, as also saith the law.
(1 Corinthians 14:35) And if they will learn any thing, let them ask their husbands at home: for it is a shame for women to speak in the church.
These verses seem to continue the subject from verse 33 of confusion in the church service. Paul seems to tack this on as an afterthought.
It seems Paul is commanding the women to not interrupt the service by asking questions during the service; they should instead ask their husbands when they get home. Perhaps the women of the culture felt free to interrupt the service and to interrupt anyone else who was speaking at the time. Perhaps the women did this more than the men.
I doubt if Paul is saying that in all cultures and at all times that women are to remain completely silent in church and that they are to have no role in the church.
(1 Corinthians 14:36) What? came the word of God out from you? or came it unto you only?
(1 Corinthians 14:37) If any man think himself to be a prophet, or spiritual, let him acknowledge that the things that I write unto you are the commandments of the Lord.
Those who are spiritually advanced are to obey these commands of Paul. Paul is not merely offering helpful suggestions for them to consider and to reject if they don't fit their situation. Yet many charismatic churches do ignore Paul's admonitions and even claim Paul is teaching them to do the very things he is telling them not to do.
(1 Corinthians 14:38) But if any man be ignorant, let him be ignorant.
If someone ignores Paul's admonitions, it is because they are ignorant, not because they are spiritually advanced.
(1 Corinthians 14:39) Wherefore, brethren, covet to prophesy, and forbid not to speak with tongues.
I can't imagine why Paul would have told them not to forbid speaking in tongues; likely they were going to ignore him anyway. I doubt they would have forbidden the speaking in tongues altogether but it seems to me Paul actually would have preferred that outcome.
Perhaps Paul was afraid that squelching the use of the gifts of the Spirit would have deadened the faith life of the Christians at large. That is what happened in the very early church when the bishops began to create a division between clergy and laity. Perhaps church should have extemporaneous participation by the church members to keep the life in the church; to keep it from become spiritually dry.
(1 Corinthians 14:40) Let all things be done decently and in order.
It seems the Corinthian church had problems with having a decent and orderly service. People interrupted the service, the poor were neglected, there were wild displays of pagan-like tongues speaking.
I've been to church services of charismatic churches having these same problems. Because they teach that these charismatic practices are good things, they ignore Paul's clear admonitions in 1 Corinthians 14. Weirdly, they use this same chapter to justify their disorderly practices.