If speaking in tongues is the ability to speak in a known language never before learned, what was its purpose? According to First Corinthians 14:21-22, speaking in tongues was a sign gift that was given for the purposes of unbelievers rather than for the edification of believers. What were sign gifts? Sign gifts were supernatural abilities that God gave to some in order to validate to unbelievers that their message was truly from God (see Acts 2:22; Second Corinthians 12:12). Back then the Bible was not yet completed. How did you know if someone claiming to be from God really was from God? God gave them sign gifts as a validation. On the Day of Pentecost, when the people heard these very unlearned Galileans speaking in their languages, and it was obvious that they had never learned that language previously, they knew that their message was from God.
So the real question is this, “Is the gift of tongues still for today?” First Corinthians 13:8 teaches clearly that tongues would one day cease. But did it? Well, after the writing of First Corinthians, tongues is never mentioned again in Scripture. In fact, Paul wrote up to 12 more books but never mentioned tongues again. In two of these books, Romans and Ephesians, Paul teaches on spiritual gifts but still does not mention speaking in tongues. Four other men, who all spoke in tongues on the Day of Pentecost, wrote books after First Corinthians but none of them ever mentioned speaking in tongues. This included John (who wrote 4 books); Peter (who wrote 2 books); as well as James and Jude (who each wrote one book).
The writer of Hebrews makes it clear in Hebrews 2:2-4, that the sign gifts that confirmed the message of the Apostles were past completed actions. The word “confirmed” is written in the aorist tense (past action). If sign gifts were still being used to validate the message of the Apostles, it would have been written in the present tense. So First Corinthians 13:8 teaches that tongues would cease and every bit of evidence says it did.
So what caused tongues to cease? As you keep reading on in First Corinthians 13:8-12, you will discover that tongues would cease when “that which is perfect comes.” Though some believe “that which is perfect” to speak of the second coming of Christ, I think it is better understood as describing the completed Scriptures. For one thing, the adjective is neuter, so we are speaking of a thing, not a person. Second, the word “perfect” is never found in Scripture speaking of the Second Coming, but it is used in James 1:25 to speak of the Bible by calling it the “perfect Law of Liberty.” So if we are to always interpret Scripture with Scripture, it would be best to see this as a reference to Scripture.
This being the case, Paul is teaching that the gift of speaking in tongues would cease with the completion of the New Testament. Back then, it was sign gifts that validated if a messenger and his message was from God. Today, it is Scripture that validates if a message is from God. And even if “that which is perfect” is a reference to the Second Coming, this would not prove that tongues is for today (but that is too detailed and too deep to explain in the confines of a written blog).