Charismatics generally hold to three different uses of tongues. First, most Charismatics argue that speaking in tongues is the initial evidence of receiving the baptism in the Holy Spirit.  They regard the historical occurrences in the book of Acts (ch. 2, 10, 19) as normative for the church for all ages. Second, tongues are to be used in public worship for the edification of the body. These public tongues must be interpreted or translated, so that the edifying message can be understood by all. (In many Charismatic churches, people blurt out “tongues” which are never interpreted.) Charismatics differ over whether or not “tongues” in the assembly are a form of direct revelation from God. The third use of tongues is speaking in tongues for private edification. This is based on a false interpretation of 1 Corinthians 14:1-4. This form of tongues is considered a private prayer language to God.
There are a number of questions relating to tongues that we want to answer. What are biblical tongues? Are tongues real human languages or unintelligible, ecstatic gibberish? Are there two types of tongues in the Bible: one for the church and one for private prayer? Are tongues revelational in nature, like prophecy, or just another method of uninspired exhortation?
The only way to define tongues biblically is to study the usage of the term by biblical writers. The Greek word glossa, translated “tongue” (pl. glossais), when not referring to the actual bodily organ called the tongue, refers either to an ethnic group (that is, a group separated by language) or to actual human languages. “The word glossa is used some thirty times in the Greek Old Testament (the Septuagint) and always its meaning is normal human language”  Our primary concern is what the term refers to when speaking of the New Testament spiritual gift of tongues. The Bible clearly teaches that the spiritual gift of speaking in tongues always refers to real, known human languages.
On the day of Pentecost, the disciples “began to speak in other tongues” (glossais, Ac. 2:4). Were they babbling unintelligible nonsense or speaking in real human languages? Because this first instance serves as a paradigm or pattern for all subsequent tongue speaking, the Holy Spirit carefully defined the nature of tongues, It is clear that the disciples were speaking real, known languages. They even spoke different dialects of the same language (e.g., the Phrygians and Pamphylians spoke different dialects of Greek).
There were dwelling in Jerusalem Jews, devout men, from every nation under heaven. And when this sound occurred, the multitude came together, and were confused, because everyone heard them speak in his own language (dialektos). Then they were all amazed and marveled, saying to one another, “Look, are not all these who speak Galileans? And how is it that we hear, each in our own language (dialektos) in which we were born?” (Acts 2:5-8).As if to emphasize that the disciples were speaking real languages and not gibberish, Luke even lists the peoples which heard their native tongues: “Parthians and Medes and Elamites, those dwelling in Mesopotamia, Judea and Cappadocia, Pontus and Asia, Phrygia and Pamphylia, Egypt and the parts of Libya adjoining Cyrene, visitors from Rome, both Jews and proselytes, Cretans and Arabs—we hear them speaking in our own tongues (glossais) the wonderful works of God” (Acts 2:9-11). In Acts 2, glossais is used by Luke interchangeably with dialektos (“the tongue or language peculiar to any people,” J. H. Thayer). The biblical account records that on three occasions the multitude said that they heard their own language being spoken. Luke even records the different national languages and regional dialects which were spoken by the disciples.
In Acts, tongues are always real, human languages. This fact is confirmed when we examine the outpouring of the Holy Spirit on the Gentiles in Acts 10:44-48. Peter says that the Gentiles “received the Holy Spirit just as we have” (v. 47). He tells the Jerusalem church that “the Holy Spirit fell on them [the Gentiles], as upon us at the beginning” (Ac. 11:15). Peter says that God gave the Gentiles “the same gift as He did unto us” (v. 17). Peter is saying that the gentiles experienced the same thing as the Jewish disciples did at Pentecost, “This likeness of experience extends not only to the fact of receiving the Spirit but to the nature of tongue-speaking in foreign languages”  Thus, there is not a shred of evidence within the book of Acts that tongues-speaking is anything but real foreign languages. But what about 1 Corinthians?
In 1 Corinthians, tongues are also real foreign languages. Let us first examine the clear passages regarding tongues and then examine the passages which are quoted by Charismatics as a justification for non-foreign language, ecstatic, private-prayer language to God.
Paul designated the gift of tongues as gene glossen, translated as “kinds of tongues” (1 Cor. 12:10) and “diversities of tongue” (1 Cor. 12:28). This term genos refers to a family, offspring, race, nation, kind, sort, and class in New Testament usage. It always designates items which are related to each other. There are many “kinds” of fish (Mt. 13:47) but they are all fish. There are several “kinds” of demons in the world (Mt. 17:21), but they are still demons. There are many “kinds” of voices (1 Cor. 14:10), but they are all voices. From this it can be concluded that there are many “kinds” of languages, but they are all languages. There are several families of languages in the world—Semitic, Slavic, Latin, etc. These are all related, in that they have a definite vocabulary and grammatical construction. Paul could not have possibly combined known, foreign languages with unknown, ecstatic utterances under the same classification. They simply are not related to each other. Thus, if there were two completely different tongue-types—known languages on the one hand, and ecstatic, babbling, private-prayer language on the other hand, as many Charismatics assert—then the Holy Spirit who cannot lie would not have used the word genos to describe tongues in 1 Corinthians chapter twelve.
Another passage which disproves the Charismatic position is 1 Corinthians 14:21-22: “In the law it is written: ‘With men of other tongues and other lips I will speak to this people; And yet, for all that, they will not hear Me,’ says the Lord. Therefore tongues [Greek: the tongues] are for a sign, not to those who believe but to unbelievers....” Here, tongues are compared to a real, foreign language (Assyrian ), showing that the Apostle Paul considered tongues to be actual languages.
This is further confirmed by the usage of the article of previous reference (hai) and the function of the inferential conjunction “therefore” (hoste). If Paul considered speaking in tongues to be an unknown utterance, he would not have used the same word twice in these two verses, especially since the meaning of glossa was clearly established in the first usage. Our contention that tongues refer to real foreign languages is supported by the Greek word used by Paul when he says that tongues must be interpreted (cf. 1 Cor. 12:10; 14:26, 28). When the word hermeneuo is not used to describe the exposition of Scripture, it simply means “to translate what has been spoken or written in a foreign language into the vernacular.”  When the word is used of the exposition of Scripture (e.g., Lk. 24:27) it is translated expound. When the word hermeneuo is used with regard to tongues it is translated to interpret. An interpreter is someone who translates a foreign language into a language understandable to the present audience.
The position is sometimes taken that the gift of interpretation is a kind of intuitive, empathetic capacity by which the mindless utterance of one member of the congregation is given intelligible meaning by another, a gift by which the preconceptual dimension in man voiced by one member is given rational, conceptual shape by another. But such a view is not only foreign to the Biblical usage of “interpret” elsewhere (hermeneuo and its compounds) but also presupposes the view of tongues we have already discussed and rejected as unbiblical. The only reason tongues-speech is unintelligible to the listeners is that they do not understand the language being spoken. But are there not passages which teach that there is a private prayer use for tongues—that tongues are to be used for private prayer to God and for private edification? The three passages commonly used to argue for two types of tongues are: Romans 8:26, 1 Corinthians 13:1; 14:2-4. The first passage actually has nothing to do with tongues: “The Spirit Himself makes intercession for us with groanings which cannot be uttered.” Unutterable or unuttered groanings obviously cannot refer to tongues.
But what about 1 Corinthians 13:1? Doesn’t this passage teach that we can pray with the tongues of angels? “If I speak with the tongues of men and of angels” (1 Cor. 14:1). It is clear from the Greek grammar (ean with the subjunctive) and the context that Paul is speaking hypothetically. “He raises it hypothetically to the most magnificent realization of it possible” —that is, to make a point. Paul is not telling the church to pray in the tongues of angels. He is saying that no matter how great your gift is, you need love. And even if it were possible to speak in the tongues of angels, it would still be a real, translatable language, not a bunch of gibberish. Linguists have the ability to look at language structure and determine noun phrases, verb phrases, adverbs, and so on. Thus, if people were really speaking in the tongues of angels, it could be determined if a real (although heavenly) language were being spoken.
The best proof text for private prayer tongues is 1 Corinthians 14:1-5.
Pursue love, and desire spiritual gifts, but especially that you may prophesy. For he who speaks in a tongue does not speak to men but to God, for no one understands him; however, in the spirit he speaks mysteries. But he who prophesies speaks edification and exhortation and comfort to men. He who speaks in a tongue edifies himself, but he who prophesies edifies the church. I wish you all spoke with tongues, but even more that you prophesied; for he who prophesies is greater than he who speaks with tongues, unless indeed he interprets, that the church may receive edification.The first thing that needs to be noted regarding this passage is that, regardless of one’s interpretation of “edifies himself” (v. 4); the tongues spoken of throughout chapter 14 are definite, real foreign languages. There is nothing within the passage or within the broader context that teaches that the tongues spoken of in verses two through four are peculiar (e.g., ecstatic gibberish), unique, or different. The tongues spoken of in verse four are real, foreign languages, just as the tongues in verse 21 and 22 are real, foreign languages. This fact is important; if one believes that 1 Corinthians 14:2-4 justifies the private use of tongues in devotions, then there is an objective test to determine if the speaker is speaking gibberish (i.e., syllabic nonsense) or a real foreign language: the private tongue-speaking could be tape-recorded and submitted to any competent linguist for verification.
Does this passage teach the private use of tongues? No. Paul is discussing edification in the assembly during public worship. He argues that he prefers prophecy over tongues because of its superior capability for the edification of the church.  When he says, “He who speaks in a tongue does not speak to men but God, for no one understands him,” he is not telling the Corinthians that they should be praying in tongues to God in private; he is emphasizing that without an interpreter, no one in the assembly understands except God.  Likewise, when Paul discusses praying and singing with the Spirit, he makes it clear that it must be interpreted, since it takes place in public worship: “Otherwise, if you bless with the spirit, how will he who occupies the place of the uniformed say ‘Amen’ at your giving of thanks, since he does not understand what you say?” (1 Cor. 14:16). There is simply not a shred of biblical evidence for the idea of private devotional tongues.
But, then, what does Paul mean when he says, “He who speaks in a tongue edifies himself”? The context indicates that Paul is describing someone who speaks in tongues in church without an interpreter. Paul is not saying that Christians should pray in tongues in private to be edified. Throughout this chapter, Paul argues again and again for the need to interpret tongues; otherwise, the church is not edified: “Since you are zealous for spiritual gifts, let it be for the edification of the church that you seek to excel. Therefore let him who speaks in a tongue pray that he may interpret” (1 Cor. 14:12-13). Since the whole thrust of chapter 14 is the edification of the body, it is probable that “edifies himself” is meant to be taken in a negative sense. To speak in tongues without an interpreter merely calls attention to oneself and does not benefit the body. Speaking in tongues in the assembly without an interpreter is a form of self-glorification.
Why is it significant that tongues-speaking refers to foreign languages and not gibberish (e.g., “Yabba-dabba-doo”)? It is significant because it gives us an objective method to determine if modern tongues-speaking is genuine, or manmade nonsense. If the Charismatic movement is truly a work of God, then anyone should be able to verify it simply by recording people speaking in tongues and having it analyzed by linguists, to see what language was being spoken. If tongues were merely the gibberish one encounters in Charismatic churches and not real languages, then tongues are not a sign to unbelievers, as Paul clearly asserts. A sign is a publicly-verifiable miracle. “Speaking in foreign languages which were not learned would certainly constitute a divine miracle; however, speaking in gibberish or in unknown sounds could easily be done by either a Christian or an unsaved person.”  Every instance in the twentieth century where Charismatic tongues-speaking was taped and analyzed by linguists revealed that modern “tongues” were not real languages but gibberish. Modern tongues-speaking doesn’t even resemble any language, structurally. “The conclusion of the linguists indicates that modern glossolalia is composed of unknown sounds with no distinguishing vocabulary and grammatical features, simulated foreign features, and total absence of language characteristics. The essential character of this new movement is therefore at variance with the biblical phenomenon of speaking in known languages.”  Thus we conclude that modern tongues-speaking contradicts the clear testimony of Scripture, as well as objective empirical findings. Here is a challenge to any Pentecostal or Charismatic: tape your church service and have the “tongues” that are spoken analyzed objectively.
There are a number of other indicators that reveal modern tongues to be a fraud. Charismatics are taught how to speak with “tongues.” They are told things such as, “Now pray audibly but don’t speak English.” Or, “Start to speak syllables—just let it flow.” Many Charismatics learn how to speak in “tongues” (gibberish) by imitating others in their church or at a conference. Do we encounter anyone in the New Testament being taught how to pray in tongues? No, the exact opposite is the case. Those who speak in tongues in the book of Acts, for example, never ask what to do, and are never told to do or say anything. In the biblical accounts people speak in tongues spontaneously. In Acts 2:4, 10:46 and 19:6, those who spoke in tongues did so with no prompting or preparation. In fact, in each case, those who spoke in tongues, prior to the moment they spoke in tongues, did not know such a thing as tongues even existed! Thus, not only is modern tongues gibberatic nonsense compared with the real foreign languages spoken in the New Testament, but also the way in which Charismatics receive tongues is completely different than that in the biblical record. 
If modern “tongues” (i.e., gibberish) are completely different than tongues in Scripture (which were real, foreign languages), what happened to real, biblical tongues? The Bible teaches that tongues and the other supernatural sign gifts ceased.
Love never fails; but if there are gifts of prophecy, they will be done away; if there are tongues, they will cease; if there is knowledge, it will be done away. For we know in part, and we prophesy in part; but when the perfect comes, the partial will be done away. When I was a child, I used to speak as a child, think as a child, reason as a child; when I became a man, I did away with childish things. For now we see in a mirror dimly, but then face to face; now I know in part, but then I shall know fully just as I also have been fully known (1 Cor. 13:8-12 NASB).Paul contrasts the revelatory gifts of prophecy, special knowledge and tongues, which by nature are piecemeal and incomplete, with the complete canon of Scripture (which was completed with the 27 books of the N.T.).
That which was to supersede the partial and do away with it was something designated “perfect.” “But when the perfect comes, the partial will be done away.” It is difficult to miss the antithetic parallel between the “partial” thing and the “perfect” (“complete, mature, full”) thing. Since the “partial” speaks of prophecy and other modes of revelational insight (v. 8), then it would seem that the “perfect,” which would supplant these, represents the perfect and final New Testament Scripture (Jas. 1:21). This is due to the fact that modes of revelation are being purposely contrasted. Thus, it makes the man of God adequately equipped to all the tasks before him (2 Tim. 3:16-17). In other words, there is a coming time when will occur the completion of the revelatory process of God. The primary objection used against this passage by Charismatics has to do with the phrase “face to face.” They argue that this expression refers to seeing Christ “face to face” at the second coming; thus, the supernatural gifts are to continue until the second coming. The problem with this interpretation is twofold. First, “face to face” is an adverbial phrase; it does not have an object.  Second, “face to face” is contrasted with a “dim mirror.” Since “face to face” is adverbial without an object, the idea that it refers to Christ must be assumed or inferred. And since Paul has been contrasting forms of revelation throughout verses 8-12, it makes much more sense to interpret “face to face” in the sense of clearness (or perspicuity), in contrast to the dim mirror (the incomplete or piecemeal).
There are other problems associated with the Charismatics’ practice of speaking in “tongues.” Rather than desiring the best gifts (1 Cor. 12:31), they seek the gift ranked dead-last in the Apostle’s enumeration (12:28). There is often speaking in “tongues” without proper interpretation (contrary to 14:28); unless this requirement is met, it does absolutely nothing to edify the church (14:4-5). The biblical requirement of speaking in turn is frequently not observed (14:27, 30); rather, a number of individuals speak at the same time (this lapse in proper church order is inexcusable, for “the spirits of the prophets are subject to the prophets,” 14:32). Furthermore, the common practice in Charismatic churches is to allow women to speak in the assembly (not a few Charismatic churches are even pastored by women). Women are absolutely forbidden to speak or teach in church but are commanded to keep silent (14:33-34).
“All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be complete, thoroughly equipped for every good work” (2 Tim. 3:16-17). Since we have a completed canon, and since the Bible is all we need for salvation, life and godliness, what purpose do modern tongues and prophecy serve? Speaking in tongues was one of the signs of an apostle (2 Cor. 12:12); once the apostles passed off the scene, there was no more need for their distinguishing signs. The historical fact that real tongues and prophecy ceased with the completion of Scripture, and the fact that modern tongues and prophecy bear no resemblance to what occurred during the days of the apostles, proves that the central distinctives of the Charismatic movement are unbiblical.