Commentary - John 12:37-43

Bird's-eye view

This section of John’s Gospel serves as a somber conclusion to the public ministry of Jesus. After a crescendo of miraculous signs, culminating in the raising of Lazarus, the evangelist John pauses the narrative to address a staggering reality: widespread unbelief. Despite overwhelming evidence, the people, and particularly their leaders, were not believing in Him. John explains that this tragic outcome was not a surprise to God, but rather the fulfillment of prophecies from Isaiah. This unbelief is presented not as a failure of God’s plan, but as a feature of it. The passage wrestles with the hard doctrine of judicial hardening, where God, in His sovereignty, gives men over to the blindness they have chosen. The issue is not a lack of evidence but a lack of heart. The passage concludes by diagnosing the root cause of this unbelief, not just in the hardened masses, but even among secret believers in the Sanhedrin. The core problem was a love for human approval that eclipsed their fear of God. They loved the glory of men more than the glory of God, a spiritual sickness that remains the central temptation for all men in every age.

In short, John is providing a theological explanation for the rejection of the Messiah. He anchors this explanation in the Old Testament, showing that God’s sovereign purposes are always fulfilled, even through human sin and rebellion. The passage is a stark reminder that faith is not a simple matter of intellectual assent to evidence, but a supernatural gift that overcomes a heart naturally bent toward self-glorification and the fear of man.

Outline

Context In John

This passage marks a major turning point in John's Gospel. Up to this point, Jesus has been engaged in a public ministry, presenting His claims through a series of "signs" and discourses. Chapter 12 began with the anointing at Bethany, a prelude to His burial, and His triumphal entry into Jerusalem, a public presentation of His kingship. The request of the Greeks to see Jesus (John 12:20-22) signaled that the hour had come for His glorification through death, and Jesus Himself declared it (John 12:23). His subsequent discourse on the nature of His death as a seed that must fall into the ground and die (John 12:24) and the voice from heaven affirming Him (John 12:28) represent the final public testimony. From this point forward, Jesus withdraws from the crowds (John 12:36b) and turns His attention to the private instruction of His disciples in the Upper Room Discourse (John 13-17). This section (12:37-43) therefore functions as John's inspired commentary on why the public ministry, despite its power, ended in rejection. It provides the theological framework for understanding everything that is about to happen in the Passion narrative.

Key Issues

The Hardening of Israel

This is one of those passages that makes modern evangelicals squirm, but it is a doctrine that is shot through the whole counsel of God. The Bible teaches two truths that we must hold in tension, without trying to reconcile them in a way that diminishes either. First, man is responsible for his sin and unbelief. The gospel is offered to all, and those who reject it are culpable. Second, God is absolutely sovereign over all things, including the salvation and condemnation of men. This passage brings us face to face with the second great truth.

When John says they "could not believe," he is not making an excuse for them. He is stating a spiritual fact. Their hearts were so calloused by sin that they were morally unable to believe. But where did this inability come from? John, quoting Isaiah, says "He has blinded their eyes and He hardened their heart." This is judicial hardening. God, as a righteous judge, sometimes punishes sin by giving people over to more sin. He confirms them in the rebellious choice their own hearts have made. This is not arbitrary; it is a just sentence. They loved the darkness, and so God gave them over to the darkness. This is a terrifying thought, but it is essential to a biblical understanding of both sin and grace. If God did not sovereignly intervene to soften hard hearts, no one would ever be saved. The fact that anyone believes is a miracle of grace; the fact that many do not is a testament to both their own sin and God's righteous judgment.

Verse by Verse Commentary

37 But though He had done so many signs before them, they still were not believing in Him,

John begins with a stark contrast. On the one hand, you have the sheer volume of evidence: "so many signs." These were not ambiguous events; they were powerful, public, undeniable miracles, from turning water into wine to raising a man from the dead. On the other hand, you have the settled state of their hearts: "they still were not believing in Him." The verb tense suggests a continuous, ongoing refusal to believe. This verse demolishes the simplistic idea that "seeing is believing." For the unregenerate heart, seeing is not enough. The problem is not with the eyes, but with the heart. Miracles can confirm faith, but they cannot create it out of whole cloth in a heart set against God.

38 so that the word of Isaiah the prophet might be fulfilled, which he spoke: “LORD, WHO HAS BELIEVED OUR REPORT? AND TO WHOM HAS THE ARM OF THE LORD BEEN REVEALED?”

John immediately explains that this tragic unbelief was not an unforeseen accident. It happened "so that" Isaiah's prophecy might be fulfilled. This is the language of divine purpose. The quote is from Isaiah 53:1, the beginning of the great prophecy of the Suffering Servant. Isaiah's lament was not just his own; it was a prophetic description of how the Messiah's own people would receive Him. The "report" is the gospel message. The "arm of the LORD" is God's power displayed in Christ. The questions are rhetorical. The answer is, "very few." Belief is not the default human response to the gospel. It requires a divine revelation, an unveiling of God's power to the soul. Without that, the report, no matter how glorious, falls on deaf ears.

39 For this reason they could not believe, for Isaiah said again,

John now drives the point home. He moves from their not believing to their inability to believe. "For this reason they could not believe." Why? Because another word from Isaiah had to be fulfilled. John is stacking up his authorities. This is not his personal opinion; this is what the prophet of God declared centuries before. The reason for their inability is found in the sovereign decree of God, spoken through His prophet.

40 “HE HAS BLINDED THEIR EYES AND HE HARDENED THEIR HEART, LEST THEY SEE WITH THEIR EYES AND UNDERSTAND WITH THEIR HEART, AND RETURN AND I HEAL THEM.”

This is the hard saying, quoted from Isaiah 6:10. In Isaiah's commissioning, God tells him that his preaching will have a hardening effect on the people. Here, John applies it directly to the ministry of Jesus. Who blinded their eyes? God did. Who hardened their heart? God did. And for what purpose? "Lest they see...understand...and return and I heal them." This is judicial hardening in its starkest form. God sovereignly withholds the grace of repentance from those whom He has judged. This is not to say that they wanted to repent and God stopped them. Rather, their hearts were already rebellious, and God, in judgment, confirmed them in that rebellion, removing any possibility of their return. He locked the door they had already slammed shut. This is a terrifying aspect of God's sovereignty, but it magnifies His glory and His mercy toward those whose eyes He chooses to open.

41 These things Isaiah said because he saw His glory, and he spoke about Him.

This is a crucial verse for our Christology. John tells us that when Isaiah wrote these words, he did so because he had seen Jesus' glory. He is referring to the vision of Isaiah 6, where Isaiah saw "the Lord sitting upon a throne, high and lifted up" (Isa 6:1). John flatly identifies that Lord, that Yahweh of the Old Testament, as the pre-incarnate Christ. This means that the one who commissioned Isaiah with this message of hardening was none other than Jesus Himself. Isaiah saw Christ's glory as the sovereign King, and it was in that context that he spoke about Him and His rejection by His own people. The entire plan of redemption, including the hardening of Israel, is Christ-centered.

42 Nevertheless many even of the rulers believed in Him, but because of the Pharisees they were not confessing Him, for fear that they would be put out of the synagogue;

John now introduces a nuance. The unbelief was not absolute. There was another group: the secret believers. Even among the "rulers," the members of the Sanhedrin, there were many who were intellectually convinced that Jesus was the Messiah. Theirs was a real, albeit deficient, belief. But it was a cowardly belief. They refused to confess Him publicly. Why? "Because of the Pharisees." They were afraid of the social and religious consequences. To be "put out of the synagogue" was to be excommunicated, to become a social and religious outcast. They had a belief that was real enough to trouble their conscience, but not strong enough to overcome their fear of man.

43 for they loved the glory of men rather than the glory of God.

Here is the final diagnosis, the root of the disease. Why did the fear of man have such a grip on them? Because their loves were disordered. They loved the doxa, the glory, the praise, the approval, the honor that comes from men, more than they loved the glory that comes from God. They were weighing two things in the balance: their reputation in the community versus their standing before God. And for them, their reputation won. This is the essence of worldliness. It is a value system that prizes the fleeting applause of sinful men over the eternal "well done" of the living God. This verse explains not only the cowardice of the rulers, but also the outright rejection of the others. At the bottom of all unbelief is a love for self-glory that refuses to bow before the glory of God in the face of Jesus Christ.

Application

This passage ought to land on us with considerable weight. The temptations described here are not unique to first-century Jewish rulers. They are the perennial temptations of the human heart, and they are particularly potent in the evangelical world today.

First, we must reckon with the hardness of the human heart. We are often tempted to think that if we just make our arguments clever enough, our presentations slick enough, or our churches attractive enough, people will naturally flock to Christ. This passage teaches us that unbelief is not an information problem; it is a heart problem. No amount of "signs" will persuade a heart that is set in rebellion. This should drive us to our knees in prayer, knowing that only a sovereign work of God's Spirit can open blind eyes and soften hard hearts. Our evangelism must be utterly dependent on God.

Second, we must examine our own hearts for the sin of the secret believers. How many Christians in our comfortable, respectable churches hold a private belief in Jesus, but refuse to confess Him in any costly way? They believe, but they will not speak up at work when Christ is mocked. They believe, but they will conform to the world's standards in their business practices or their entertainment choices. They believe, but they will remain silent on the great moral evils of our day, like abortion or sexual rebellion, for fear of being "put out of the synagogue" of polite society. This is the fear of man, and it is a snare.

And the root of it all is the love of human glory. We want to be liked. We want to be respected. We want a seat at the table. We want the world to think we are reasonable, compassionate, and sophisticated. We want the glory of men. But the gospel calls us to die to all that. It calls us to seek the glory that comes from God alone. It calls us to confess Christ openly, to bear His reproach gladly, and to count our reputation, our careers, and our social standing as loss for the excellency of knowing Him. The question this passage leaves us with is a sharp one: Whose applause are you living for?