Paul then moves from elevating prophecy to degrading tongues speaking without interpretation. The whole tenor of Paul in 1 Cor. 14 is against the pursuit of tongues without interpretation, which does not edify the church. Instead, he presses the pursuit of the gift that builds up the church. Paul argues that tongues speaking without interpretation is practically useless in church. But prophesying or teaching is useful. The reason—prophesying is intelligible while tongues speaking without interpretation is unintelligible.
6 Now, brothers, if I come to you speaking in tongues, how will I benefit you unless I bring you some revelation or knowledge or prophecy or teaching? 7 If even lifeless instruments, such as the flute or the harp, do not give distinct notes, how will anyone know what is played? 8 And if the bugle gives an indistinct sound, who will get ready for battle? 9 So with yourselves, if with your tongue you utter speech that is not intelligible, how will anyone know what is said? For you will be speaking into the air. (1 Cor. 14:6-9).
Hence, speaking in tongues is useless in church if nobody understands what you are saying.
Further, Paul explains the need to know the meaning of the spoken tongues (v. 10). He cites the speaking in tongues in the context of speaking in languages of the world. “There are doubtless many different languages in the world, and none is without meaning, but if I do not know the meaning of the language, I will be a foreigner to the speaker and the speaker a foreigner to me” (vv. 10-11). He uses the world of languages to illustrate speaking in tongues. Note Paul’s words—“none is without meaning.” Hence, one must know the meaning of the tongues by interpreting it. All tongues speaking should be interpreted, so that all can know the meaning of the tongues.
Thus, Paul wrote, “So with yourselves, since you are eager for manifestations of the Spirit, strive to excel in building up the church” (v. 12). How do they do that? By ensuring the interpretation of tongues. When you interpret the tongues, people will understand its meaning. When they understand its meaning, they will be edified.
“Therefore,” Paul wrote, “One who speaks in tongues should pray for the power to interpret” (1 Cor. 14:13). The reason for this instruction is apparent. The interpretation of tongues will build up the church. The spiritual growth of the church is the central purpose of all spiritual gifts, including the gift of tongues.
Paul then hammers the importance of understanding the tongues spoken.
14 For if I pray in a tongue, my spirit prays but my mind is unfruitful. 15 What am I to do? I will pray with my spirit, but I will pray with my mind also; I will sing praise with my spirit, but I will sing with my mind also. 16 Otherwise, if you give thanks with your spirit, how can anyone in the position of an outsider say “Amen” to your thanksgiving when he does not know what you are saying? 17 For you may be giving thanks well enough, but the other person is not being built up. 18 I thank God that I speak in tongues more than all of you. 19 Nevertheless, in church I would rather speak five words with my mind in order to instruct others, than ten thousand words in a tongue.
Indeed, what is the use of praying in tongues when you do not know what you are praying? What is the benefit of praising in tongues in church when others do not know what you are praising? Interpreting the tongues brings understanding; and with understanding comes edification.
Note Paul’s purpose, “to instruct others” (v. 19). To instruct others is to build up others. To build up others is to bring good to others. Paul would rather speak a few words “with my mind,” i. e., with the understanding, than many words in a tongue that nobody understands. The motive is obvious. He wants to edify the church.