The Theology of Unbelief

This isn’t the first time we hear about God’s hardening hearts and man’s inability to believe. Moses, in one of his final charges to Israel, told them,

You have seen with your own eyes everything the Lord did in Egypt to Pharaoh, to all his officials, and to his entire land. You saw with your own eyes the great trials and those great signs and wonders. Yet to this day the Lord has not given you a mind to understand, eyes to see, or ears to hear. (Deut 29:2-4)

This same language is picked up in Isaiah 6. God gives Isaiah the task of sharing his word with the children of Israel and says that Isaiah’s message to them will be like this:

Keep listening, but do not understand; keep looking, but do not perceive. Make the minds of these people dull; deafen their ears and blind their eyes; otherwise they might see with their eyes and hear with their ears, understand with their minds, turn back, and be healed. (Isa 6:9-10)

John says the unbelief of the Jews is the continued fulfillment of the words of Isaiah. They do not believe because God has not called them to believe. In fact, he has hardened their hearts even more than they already were. You could translate John 12:39 as: “They were powerless to believe” or “It was not possible for them to believe.” What we see here are two interwoven truths in John’s explanation of unbelief.

First, belief is not possible without God’s direct work in man’s heart. John Calvin explains: “Faith is not born in the ordinary human faculties but is a unique and rare gift of God” (John, 310). We see this clearly in John’s quotation of the end of Isaiah’s first prophecy: “To whom has the arm of the Lord been revealed?” (v. 38). God must reveal himself. God must take the initiative in salvation. God calls men to Jesus and saves them.

The second truth we see is that God can for his own purposes choose to harden those whom he chooses to harden (Rom 9:14-18). For his own reasons God chose to harden the already sinful, hard hearts of the Jews. We cannot completely understand God’s purpose in calling some to faith and not others, but we submit to his authority and recognize the Potter has the right to mold the clay however he sees fit. We are given a little glimpse as to God’s purpose in hardening the Jews. The book of Acts ends with several Jews coming to speak with the apostle Paul while he was imprisoned in Rome. He preached a sermon to them that went from morning until evening. The reaction was mixed: some believed, some didn’t, and a number were uncertain. Paul quoted Isaiah 6:10 about God’s hardening the hearts of the Jews, and he gives us a glimpse as to why: “Therefore, let it be known to you that this salvation of God has been sent to the Gentiles; they will listen” (Acts 28:28). In the case of the Jews, one reason God confirmed them in their rejection and unbelief was that he was going to spread the gospel to the Gentiles. God has a plan. He’s in control, and whatever he chooses to do in a person’s heart is wise and just.

Whatever we do, we must not assign blame to God. D. A. Carson helps us put God’s hardening in its proper perspective:

God’s judicial hardening is not presented as the capricious manipulation of an arbitrary potentate cursing morally neutral or even morally pure beings, but as a holy condemnation of a guilty people who are condemned to do and be what they themselves have chosen. (John, 448–49)

At some point we reach the end of our human understanding, and we are left to trust the goodness of God and recognize our finite comprehension of his way and plan. We need to affirm both truths John reveals in this passage, acknowledging that the Bible never pits divine sovereignty against human responsibility.

In Isaiah 6 God tells Isaiah his message would be about deaf ears and darkened hearts—which is discouraging—but if you keep reading, you find something hopeful. In verse 11 Isaiah asks God, “Until when, Lord?” He’s asking, “How long will I preach a message that simply serves to harden the hearts of those who hear it?” The Lord’s answer begins with the word until. Until! That means the hardening is temporary. God will call people to faith in him. That hope motivates evangelism. The sovereignty of God over belief and unbelief gives us confidence to share the gospel. If you don’t think God is sovereign, why pray for those who don’t believe? We need to see that God is God, and we are not. As God, he has the authority and power to give faith to whomever he chooses.

If God is sovereign over belief and unbelief, then it’s his prerogative to determine who will and will not respond to the gospel. We see Peter preach, and three thousand get saved. Paul saw hundreds, even thousands, turn in faith to Jesus, and we think God has also called us to preach the gospel. Yet God also used Moses and Isaiah and Ezekiel to share his message. If we judged them numerically, we’d consider them failures. The real question is, Can we continue to be faithful even if it appears that what we are doing is failing? Can we persist in sharing the gospel even if it takes us—like it took Adoniram Judson, the Baptist missionary to Burma—six years to see someone converted?

What we can’t do is use this passage as an excuse not to share the gospel. That would be sin. A lack of evangelism is laziness. A lack of fruit in evangelism is not. Our goal needs to be biblically informed methods and a Christ-centered, theologically accurate understanding of the gospel. We leave the results up to God.

Not everyone in our passage rejects the gospel. In the summary of Jesus’s message, he promises that those who believe in him will not remain in darkness (v. 46) but will have eternal life (v. 50). Belief in Jesus is not a sentimental salve for our guilt-ridden consciences.

Genuine belief brings radical, complete, and lasting transformation of the whole person from the inside out.

There is one final group of people who seem to fall somewhere between belief and unbelief. They believe in Jesus—in some way—but are unwilling to confess that belief (v. 46). We might think they’re merely shy or immature, but verse 43 tells us what motivates their decision. They love the glory that comes from man more than the glory that comes from God. What a stark contrast from the genuine belief of Isaiah, who saw the glory of God and placed his faith in Jesus Christ (v. 41). These silent, pseudo-believers are drawn to Jesus in some sense, but they value earthly applause more than Jesus, revealing a shallow, empty faith.

Jesus has no secret followers. The New Testament never mentions this category. God calls those who believe to be baptized, join a church, and participate in the Lord’s Supper—all public expressions of a new internal reality. If you think you can be a secret follower, then you’re deceived (v. 47). Jesus goes on to say that the Father will judge them on the last day. Some listen to the Word but do not follow it. They are Sunday Christians. They may come by after the service and thank the preacher for the message, but they do not obey God’s Word. They do not follow Jesus Christ.

John wrote his Gospel to help us believe. He didn’t provide us with an excuse for unbelief. This teaching on unbelief follows Jesus’s pleading words to “believe in the light” (v. 36). This passage is about God’s power to save, so trust him to save. Ask him to save. Tell people he can save. The most rigid unbelief shatters like glass when God swings his mighty hammer of grace. God is sovereign over unbelief, which means unbelief must bow before him. Unbelief cannot say no when God says yes. Someone’s unbelief may seem like a roadblock too big to navigate, but God is bigger than unbelief. Trust him, pray to him, share the gospel, and then see the roadblock crumble as his grace sweeps in.