1 Corinthians 14:1 Pursue love, yet desire earnestly spiritual gifts, but especially that you may prophesy. 2 For one who speaks in a tongue does not speak to men but to God; for no one understands, but in his spirit he speaks mysteries. 3 But one who prophesies speaks to men for edification and exhortation and consolation. 4 One who speaks in a tongue edifies himself; but one who prophesies edifies the church. 5 Now I wish that you all spoke in tongues, but even more that you would prophesy; and greater is one who prophesies than one who speaks in tongues, unless he interprets, so that the church may receive edifying. ... 12 So also you, since you are zealous of spiritual gifts, seek to abound for the edification of the church. 13 Therefore let one who speaks in a tongue pray that he may interpret. 14 For if I pray in a tongue, my spirit prays, but my mind is unfruitful. 15 What is the outcome then ? I will pray with the spirit and I will pray with the mind also; I will sing with the spirit and I will sing with the mind also. 16 Otherwise if you bless in the spirit only, how will the one who fills the place of the ungifted say the "Amen " at your giving of thanks, since he does not know what you are saying? 17 For you are giving thanks well enough, but the other person is not edified. 18 I thank God, I speak in tongues more than you all; 19 however, in the church I desire to speak five words with my mind so that I may instruct others also, rather than ten thousand words in a tongue.
1 Corinthians 14:26 What is the outcome then, brethren? When you assemble, each one has a psalm, has a teaching, has a revelation, has a tongue, has an interpretation. Let all things be done for edification. 27 If anyone speaks in a tongue, it should be by two or at the most three, and each in turn, and one must interpret; 28 but if there is no interpreter, he must keep silent in the church; and let him speak to himself and to God. 29 Let two or three prophets speak, and let the others pass judgment. 30 But if a revelation is made to another who is seated, the first one must keep silent. 31 For you can all prophesy one by one, so that all may learn and all may be exhorted; 32 and the spirits of prophets are subject to prophets; 33 for God is not a God of confusion but of peace, as in all the churches of the saints. … 39 Therefore, my brethren, desire earnestly to prophesy, and do not forbid to speak in tongues. 40 But all things must be done properly and in an orderly manner.
1 Corinthians 14 is kind of a nuts-and-bolts, here's-how-you-do-it chapter. It's also the epitome of Paul's shaggy writing style – covering lots of ground, winding here and there, briefly tossing in multiple miscellaneous ideas. Paul mixed some detailed teaching about the purposes and usages of two (actually, three) spiritual gifts with some general information about what churches did when they assembled (hint … if you read 1 Corinthians 14 expecting some sort of proto-liturgy, you'll be disappointed and/or puzzled). What emerges from this passage and passages such as Ephesian 5:18-19, Colossians 3:16 and Hebrews 10:24-25 are several common elements: honoring God with thanks and praise; encouraging and building up God's people; all of God's people contributing to these goals; the Holy Spirit being a sort of Producer-Director-Playwright, writing, and directing a sort of drama in which all the assembled believers are at once audience and actors.
Ephesians 5:18 And do not get drunk with wine, for that is dissipation, but be filled with the Spirit, 19 speaking to one another in psalms and hymns and spiritual songs, singing and making melody with your heart to the Lord;
Colossians 3:16 Let the word of Christ richly dwell within you, with all wisdom teaching and admonishing one another with psalms and hymns and spiritual songs, singing with thankfulness in your hearts to God.
Hebrews 10:24 and let us consider how to stimulate one another to love and good deeds, 25 not forsaking our own assembling together, as is the habit of some, but encouraging one another; and all the more as you see the day drawing near.
When, in 1 Corinthians 12, Paul taught that every believer is an essential part of the Body of Christ, he wasn't spouting a beautiful-sounding, hollow platitude. He was describing how the Body of Christ was and is meant to function. Everyone contributing; everyone receiving.
Back to 1 Corinthians 14, verses 18-19 and verse 28 hint at a private and personal usage for speaking in tongues. Paul's focus in this chapter, however, is what is done in assemblies of believers. Basically, in verse 11 Paul gives what amounts to an equation: (Speaking in Tongues) + (Interpretation) = Prophecy. So, then, what is the purpose of Prophecy (and, therefore, of a message in Tongues plus Interpretation)? Verse 3 gives the answer: edification (build up other believers); exhortation (urge fellow believers to action); consolation (comfort and encouragement during troubling times). Giving power and authority to these purposes is the fact that prophetic messages - if genuine - are from God. For this reason, Paul attached particular importance in this chapter to prophecy. It should be pointed out – this being a common misunderstanding (plus or minus a bit of Cessationist agenda) – that prophecy is not skillful or "inspired" teaching or preaching - teaching is another, distinct, spiritual gift. A comparison of Acts 13:1 and 2 Timothy 1:11 suggests that one of Paul's gifts – before and after being called to be an apostle – was teaching. So he would have known and lived this difference first-hand.