"For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful."
1 Corinthians 14:14
Many interpret this verse to mean that when Paul prayed in the Spirit, he used a "heavenly tongue" and did not himself know what he was praying. This raises an important question. How would Paul know if his prayer was answered?
What is Paul really saying in 1 Corinthians 14:14? Please allow me to rephrase the verse in William’s English: "If I pray in a language those around me do not know, I might be praying with the Spirit, but my thoughts would be unfruitful for those listening." Paul is adamant that if we pray out loud, we should either pray so others around us can understand or else keep quiet! Notice the next few verses: "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. 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" 1 Corinthians 14:15,16. According to this text, the one who has the problem with understanding is the listener and not the speaker. If you have ever prayed with someone who is offering a prayer in a language unknown to you, then you know what Paul meant when he said it is difficult for you to say "Amen" (meaning "so be it") at the end of the prayer. Without an interpreter, you have no idea to what you are saying “amen” to.
It is obvious from the context of 1 Corinthians 14 that the purpose of speaking in tongues, or foreign languages, is to communicate the gospel and thereby edify the church. If the listeners do not understand the spoken language they cannot be edified. Consequently, if there is no interpreter, the speaker is simply speaking into the air and the only ones present who know what is being said are God and him- self. This is the clear meaning of the often understood verse 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."
Paul emphasizes again that the languages spoken need to be understood by the hearers or else the one who wants to share the gospel needs to sit quietly and just pray to himself. "So likewise ye; except ye utter by tongue words easy to be understood, how shall it be known what is spoken for ye shall speak into the air." "But if there be no interpreter, let him keep silence in the church; and let him speak to himself, and to God." Verses 9, 28. Clearly, as we see in Acts, chapter 2, the entire purpose of tongues is to share the gospel with all languages and people. As a matter of fact, in Acts 2:8 where it says, “And how hear we every man in our own tongue, wherein we were born”, many margins in the KJV will have a footnote by the word “tongue” which will read “language”.
Some have thought that Paul did indeed pray a heavenly language or the language of angels when he says in 1 Corinthians 13:1, “Though I speak with the tongues of men and of angels.” If you read this verse in its context, you will see that the word "though" means "even if." For example, Paul also said in verse 2, "Though I have all faith ..." He did not have all faith. And verse 3 adds, "Though I give my body to be burned". Paul was beheaded, not burned. So we can see that Paul here used the word "though" to mean "even if."