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.  But he that prophesieth speaketh unto men to edification, and exhortation, and comfort.  He that speaketh in an unknown tongue edifieth himself; but he that prophesieth edifieth the church. (1 Corinthians 14:2-4 KJVS)
(Calvin’s Commentary 1 Corinthians 14:2)
For he that speaketh in another 808 tongue, speaketh, etc. He now shows from the effect, why it was that he preferred prophecy to other gifts, and he compares it with the gift of tongues, in which it is probable the Corinthians exercised themselves the more, because it had more of show connected with it, for when persons hear a man speaking in a foreign tongue, their admiration is commonly excited. He accordingly shows, from principles already assumed, how perverse a thing this is, inasmuch as it does not at all contribute to the edifying of the Church. He says in the outset — He that speaketh in another tongue, speaketh not unto men, but unto God: that is, according to the proverb, “He sings to himself and to the Muses.” 809 In the use of the word tongue, there is not a pleonasm, 810 as in those expressions — “She spake thus with her mouth,” and “I caught the sound with these ears.” The term denotes a foreign language. The reason why he does not speak to men is — because no one heareth, that is, as an articulate voice. For all hear a sound, but they do not understand what is said.
He speaketh in the Spirit — that is, “by a spiritual gift, (for in this way I interpret it along with Chrysostom.) He speaketh mysteries and hidden things, and things, therefore, that are of no profit.” Chrysostom understands mysteries here in a good sense, as meaning — special revelations from God. I understand the term, however, in a bad sense, as meaning — dark sayings, that are obscure and involved, as if he had said, “He speaks what no one understands.”
(Calvin’s Commentary 1 Corinthians 14:3)
He that prophesieth, speaketh unto men “Prophecy,” says he, “is profitable to all, while a foreign language is a treasure hid in the earth. What great folly, then, it is to spend all one’s time in what is useless, and, on the other hand, to neglect what appears to be most useful!” To speak to edification, is to speak what contains doctrine fitted to edify. For I understand this term to mean doctrine, by which we are trained to piety, to faith, to the worship and fear of God, and the duties of holiness and righteousness. As, however, we have for the most part need of goads, while others are pressed down by afflictions, or labor under weakness, he adds to doctrine, exhortation and consolation It appears from this passage, and from what goes before, that prophecy does not mean the gift of foretelling future events: but as I have said this once before, I do not repeat it.
Every Pentecostal church I’ve ever been to, claims to be a “full gospel” church. And if you were to ask them what that means; they will tell you, “it means; We speak in tongues.” These tongues they speak of are not spoken in any known foriegn language either, these are tongues that are without known language. And for this reason, they consider themselves to be full gospel.
In fact, many will tell you, that anyone who does not speak in tongues, is without the Holy Spirit. Because like the Jews of Jesus’ day, these Pentecostal and many Charasmatic cults, also seek a sign.
(Calvin’s Commentary on 1 Corinthians 14:3)
He that speaketh in another tongue, edifieth himself. In place of what he had said before — that he speaketh unto God, he now says — he speaketh to himself But whatever is done in the Church, ought to be for the common benefit. Away, then, with that misdirected ambition, which gives occasion for the advantage of the people generally being hindered! Besides, Paul speaks by way of concession: for when ambition makes use of such empty vauntings, 811 there is inwardly no desire of doing good; but Paul does, in effect, order away from the common society of believers those men of mere show, who look only to themselves.
Then certain of the scribes and of the Pharisees answered, saying, Master, we would see a sign from thee.  But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:  For as Jonas was three days and three nights in the whale’s belly; so shall the Son of man be three days and three nights in the heart of the earth.  The men of Nineveh shall rise in judgment with this generation, and shall condemn it: because they repented at the preaching of Jonas; and, behold, a greater than Jonas is here. (Matthew 12:38-41 KJVS)
Calvin’s interpretation is consistent with the teachings of Christ.
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. (1 Corinthians 14:5 KJVS)
(Calvin’s Commentary on 1 Corinthians 14:5)
I would that ye all spake with tongues Again he declares that he does not give such a preference to prophecy, as not to leave some place for foreign tongues. This must be carefully observed. For God has conferred nothing upon his Church in vain, and languages were of some benefit. 812 Hence, although the Corinthians, by a misdirected eagerness for show, had rendered that gift partly useless and worthless, and partly even injurious, yet Paul, nevertheless, commends the use of tongues. So far is he from wishing them abolished or thrown away. At the present day, while a knowledge of languages is more than simply necessary, and while God has at this time, in his wonderful kindness, brought them forward from darkness into light, there are at present great theologians, who declaim against them with furious zeal. As it is certain, that the Holy Spirit has here honored the use of tongues with never-dying praise, we may very readily gather, what is the kind of spirit that actuates those reformers, 813 who level as many reproaches as they can against the pursuit of them. At the same time the cases are very different. For Paul takes in languages of any sort — such as served merely for the publication of the gospel among all nations. They, on the other hand, condemn those languages, from which, as fountains, the pure truth of scripture is to be drawn. An exception is added — that we must not be so taken up with the use of languages, as to treat with neglect prophecy, which ought to have the first place.
Unless he interpret. For if interpretation is added, there will then be prophecy. You must not, however, understand Paul to give liberty here to any one to take up the time of the Church to no profit by muttering words in a foreign tongue. For how ridiculous it were, to repeat the same thing in a variety of languages without any necessity! But it often happens, that the use of a foreign tongue is seasonable. In short, let us simply have an eye to this as our end — that edification may redound to the Church.
The use of the word “tongues” in 1 Corinthians 14, is the Greek word; “gloce’-sah” which means; the language or dialect used by a particular people distinct from that of other nations.
Of course speaking in tongues was a gift from God. How else could the apostles spread the Gospel with only one language…And here is the support for this statement:
And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.  And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven.  Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language.  And they were all amazed and marvelled, saying one to another, Behold, are not all these which speak Galilaeans?  And how hear we every man in our own tongue, wherein we were born?  Parthians, and Medes, and Elamites, and the dwellers in Mesopotamia, and in Judaea, and Cappadocia, in Pontus, and Asia,  Phrygia, and Pamphylia, in Egypt, and in the parts of Libya about Cyrene, and strangers of Rome, Jews and proselytes,  Cretes and Arabians, we do hear them speak in our tongues the wonderful works of God. (Acts 2:4-11 KJVS)
See for yourself, every man heard what was being said in his own language, and then the regions from which each man dwelt is listed right there in the text.
Note what is said in verse 7, “are not all these which speak Galilaeans?”
One reason for the crowd’s surprise was the prejudice with which Judeans typically viewed Galileans in those days (John 1:46; 7:15). Without real justification (see for example chapter 1 of ), Judeans saw Galileans as uneducated and provincial. Since Jesus was from Galilee (Matt. 21:11), as were many of his disciples, one way to insult the group would have been to dismissively lump them together as “Galileans.” This was a way of implying that they were a group of yokels. Because of the anti-Galilean prejudice, some were surprised to hear Jesus’ disciples proclaiming the mighty works of God with such authority.
(Commentary by Doug Ward)
Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth.  But shun profane and vain babblings: for they will increase unto more ungodliness.  And their word will eat as doth a canker: of whom is Hymenaeus and Philetus; (2 Timothy 2:15-17 KJVS)
Hymenaeus and Philetus were heretics, Hymenaeus being one of the opponents of Paul, and Philetus being Hymenaeus’ disciple. These are those who made shipwreck their faith.
And I thank Christ Jesus our Lord, who hath enabled me, for that he counted me faithful, putting me into the ministry;  Who was before a blasphemer, and a persecutor, and injurious: but I obtained mercy, because I did it ignorantly in unbelief.  And the grace of our Lord was exceeding abundant with faith and love which is in Christ Jesus.  This is a faithful saying, and worthy of all acceptation, that Christ Jesus came into the world to save sinners; of whom I am chief.  Howbeit for this cause I obtained mercy, that in me first Jesus Christ might shew forth all longsuffering, for a pattern to them which should hereafter believe on him to life everlasting.  Now unto the King eternal, immortal, invisible, the only wise God, be honour and glory for ever and ever. Amen.  This charge I commit unto thee, son Timothy, according to the prophecies which went before on thee, that thou by them mightest war a good warfare;  Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck:  Of whom is Hymenaeus and Alexander; whom I have delivered unto Satan, that they may learn not to blaspheme. (1 Timothy 1:12-20 KJVS)
The light of God is the knowledge of God. And darkness is ignorance. Be about the bisuness of Light.