It is written in the law, By people of other tongues, and by strange lips, will I speak to this people; and neither thus will they hear me, saith the Lord.
Paul has just told the Corinthians to stop thinking like children. He now backs that rebuke with a line from Israel's own scriptures. The words are not a promise but a threat. That changes how the Corinthians should value tongues.
The quotation comes from the prophet Isaiah. Yet Paul introduces it as written in the law. That is not unusual.
The term "law" is sometimes used in the New Testament as a name for other parts of the Old Testament besides the first five books. The Lord said, "Is it not written in your Law, 'I said, you are gods'?" when the quotation was from the Psalms. John 10:34: similarly 1 Corinthians 14:21.
The appeal is made to strengthen an argument he has already been making on other grounds.
"In the law it is written," and so on. This appeal to the law is made (like the earlier one in chapter 9:9) to support his previous reasoning. He had appealed to natural usage and experience; he now makes this general reference to the earlier testimony of the Spirit — not to set up a historical parallel, but to show still more conclusively that the gift of tongues is by its nature unsuited to practical fellowship in the Spirit.
In Isaiah the strange speech was the speech of invaders. God had taught His people in plain words, and they refused it. So He would speak to them another way.
He would punish them, not with the childlike instruction they had despised, but with the foreign tones of enemies. They would not have His words of rest for the weary; they had to have a nation they did not understand. It was a judgment on their unbelief.
A foreign tongue in Israel's ears was therefore never a mark of favour.
Whenever God's people came into contact with foreign tongues, they had gone all wrong. If Israel had stayed faithful, such strange sounds would have stayed far away. They were let loose on them when they left their true place. The Corinthians would do well to consider this. For Israel, foreign tongues had no good connection. They might remind them of their folly and evil. They were in no way an honour to the Jews.
The verse ends with a refusal. God speaks in this startling way, and still the people close their ears. The same thing happened in the days of the apostles.
Verse 21 quotes Isaiah 28:11-12. Those words describe how foreign nations ruled over Israel and humbled them, because of their proud rebellion against God. God would use foreign tongues to humble them, not to exalt them. By this means He sought to wake them from their unbelief, yet they would not hear. Now God had given Israel a fresh sign in the speaking with tongues. Gentile languages now carried the gospel of grace. This showed that the gospel was not only for Israel, but for the whole world. So it was a sign for Jews above all. God gave it for the time being, to establish Christianity as being of God. And unbelieving Israel still would not hear.
Even where the sign did not convert, it settled the hearer's responsibility.
In the day of Israel's failure, when the prophets had erred, God spoke to them in the tongues of foreigners. It was a sign of the unbelief of those who would not hear the plain word of God. So the use of the gift of tongues at the beginning of Christianity was a sign, not to believers, but to unbelievers. It left the hearer without excuse.
The Corinthians were treating as a delight the very thing God had used as a warning to a rebellious nation.
What perversity, then, in the saints at Corinth! God was speaking in prophecy to build them up. They turned away from that to tongues they could not understand! As Christians, they took pleasure in what had been God's solemn threat to His ancient people for their stubborn refusal! The apostle never despises a tongue in its own place and season, here or anywhere. God intended it as a sign for unbelievers. The mistake was to bring it in among believers, who could not profit by it. That was both unintelligent and unloving.
God Himself was the speaker behind these strange sounds. That settles who the sign was for.
It was God who both worked and spoke by this gift. But He did it strangely — just as, in judgment on Israel, He had filled their ears with the foreign speech of the invaders He appointed to punish His land. Tongues, then, were for a sign. But believers need no sign. The truth is in them, and by grace they know the Lord on whom they call. Signs are meant to work by contrast. Their strangeness wakes up attention to truth that was either never known before, or forgotten through unfaithfulness. But prophecy is not a sign. It is instead an expected provision of the God of all grace, to supply His children's spiritual needs.
- Sign in the law. Paul calls Isaiah's words "the law." The New Testament uses that title for other parts of the Old Testament as well, not only the first five books.
- Sign of judgment. In Isaiah, foreign speech meant enemy armies. God's people had refused His plain teaching, so He punished them with strange tongues.
- Sign refused. The quotation ends in failure. Israel would not hear then. Unbelieving Israel still would not hear when tongues came again, and the hearer had no excuse.
- Sign misplaced. God had used tongues as a threat to unbelievers. The Corinthians prized them among believers, and so lost the profit of prophecy.
- Sign for outsiders. Believers need no sign, because they already know the Lord. Signs wake up those outside. Prophecy feeds those inside.
So that tongues are for a sign, not to those who believe, but to unbelievers; but prophecy, not to unbelievers, but to those who believe.
Paul has just quoted Isaiah's warning: God would speak to His people through foreign lips. Now he sorts the two gifts Corinth argued over by their audience — and that decides how a meeting should run.
Commentators see here Scripture's own dividing line. Some gifts build up; others are signs. That difference explains why one kind could be withdrawn and the other never.
Before I go on, note that the gifts are of two kinds. The first kind serves to awaken souls and to gather the Church. The second kind is a sign to the world — a sign that God is present in the Person of the Spirit in the Church... This distinction is important. Nothing needed for the conversion of souls and the building up of the saints can ever fail. But it is easy to see how God might withdraw what was an ornament to the Church, and a sign that she was acceptable to Him, when the Church is unfaithful.
The word "Thus" ties the verse back to Isaiah 28. There, strange speech was no compliment to Israel.
He quotes Isaiah 28:11-12 loosely, to draw a healthy lesson for the Corinthian saints. In that passage God warns the Jews, who were slow to listen to His prophets, that He would speak to them with the stammering lips of foreigners. Such a tongue speaking to Israel was a sign of their humiliation, and of God's judgment. What perversity, then, in the saints at Corinth! They turned away from God speaking in prophecy to build them up, and turned to tongues they could not understand. As Christians they took pleasure in what had been God's solemn threat to His ancient people for their stubborn refusal.
God gave the sign again in a new setting. Israel answered the same way.
Now God had given Israel a fresh sign in speaking with tongues. Gentile languages were used to preach the gospel of grace, showing that the gospel was not only for Israel, but for all the world. So it was a sign for the Jews in particular, given for a time, to establish Christianity as being of God. And unbelieving Israel still would not hear.
Why does the verse rule believers out as the audience for a sign?
Tongues then were for a sign. But believers need no sign. The truth is in them, and they know, through grace, the Lord on whom they call. Signs are meant to work by contrast. Their strangeness wakes up attention to truth that was never known before, or that has been forgotten through unfaithfulness. But prophecy is not a sign. It is what the God of all grace is expected to provide, to supply His children's spiritual needs.
The verse is a rebuke as much as a definition. Corinth used the outward gift on the wrong audience, and slighted the gift meant for them.
The Corinthians were using them for display among believers — completely wrong and unintelligent. "But prophesying" — the very thing they really slighted — "does not serve unbelievers but believers." This is its direct use.
Put a stranger in the room, and the two gifts do opposite things.
In contrast to tongues, the gift of prophecy serves not only the unbeliever but the believer. When the saints come together in one place, tongues used without an interpreter would lead an unbeliever, or an untaught person, to conclude that the assembly was mad. Prophesying does the opposite. It would convict the conscience of an unbeliever, bring the secrets of his heart into the open, and convince him that he was in the presence of God.
Translations differ in the second half of the verse. Kelly calls the added verb needless, though he thinks the translators were right not to call prophecy a sign:
The common English version needlessly introduces "serves" in the second half of verse 22. Still, I think it is right not to read "sign" together with prophesying. Prophesying differs in its very nature from the powers that truly bear that name, like a tongue or a miracle... We could just as well say tongues are a sign for the unbelieving, and prophesying for those who believe.
- Two audiences. Scripture splits the gifts in two: signs aimed at the world, and gifts that build up the saints. This verse is the dividing line.
- A sign of judgment. In Isaiah, foreign speech meant humiliation and judgment for Israel. Corinth was taking pleasure in what had been a threat.
- A sign reaches outward. A sign works by strangeness. It wakes up someone who is not listening. Believers already know the Lord they call on.
- Prophecy reaches inward — and further. Its direct object is God's people, yet it can also lay bare an outsider's heart and convince him God is present.
- Misplaced, a gift looks like madness. Tongues used among believers made the assembly look insane. The sign meant for outsiders was wasted on the wrong room.