John 12:35-43, “So Jesus said to them, “The light is among you for a little while longer. Walk while you have the light, lest darkness overtake you. The one who walks in the darkness does not know where he is going. While you have the light, believe in the light, that you may become sons of light.” When Jesus had said these things, he departed and hid himself from them. Though he had done so many signs before them, they still did not believe in him, so that the word spoken by the prophet Isaiah might be fulfilled: “Lord, who has believed what he heard from us, and to whom has the arm of the Lord been revealed?” Therefore they could not believe. For again Isaiah said, “He has blinded their eyes and hardened their heart, lest they see with their eyes, and understand with their heart, and turn, and I would heal them.” Isaiah said these things because he saw his glory and spoke of him. Nevertheless, many even of the authorities believed in him, but for fear of the Pharisees they did not confess it, so that they would not be put out of the synagogue; for they loved the glory that comes from man more than the glory that comes from God.”

It was a dark night in Jerusalem. At least it was dark in the Prophet Isaiah’s heart, for the King had died. King Uzziah had ruled Judah for 52 years; a time characterized mostly by godliness and divine blessing. But now Uzziah was dead, and Isaiah entered the temple seeking light for the darkness of his grief and dismay. What happened that night would determine the course of Isaiah’s life. Isaiah 6:1 tells us, “In the year that King Uzziah died I saw the Lord sitting upon a throne, high and lifted up; and the train of his robe filled the temple.”

As John the Apostle draws down the curtain on the ministry of Jesus before the Cross, he thinks of Isaiah. For, through the mystery of the inspiration of Scripture, John had come to realize that in Isaiah’s vision of the Lord, the 8th century B.C. Prophet had seen the Lord Jesus. John 12:41 states, “Isaiah said these things because he saw His glory and spoke of Him.” The long-ago experience of Isaiah, a pivotal moment in the Old Testament, was focused on what would later happen to the Messiah. For, like Isaiah, Jesus spoke of light to the world in darkness and of darkness that would seek to put out that light.

The Offer of Light

John 12:35-36 records the final public appeal of Jesus to God’s ancient people Israel. John 12:36 explains, “He departed and hid himself from them,” and He would not be seen publicly until His trial and crucifixion. The final words of any great man are important, but the last public teaching of Jesus is especially significant. It forms a summary of His entire message as presented to John. John 12:35 says, “So Jesus said to them, “The light is among you for a little while longer. Walk while you have the light, lest darkness overtake you. The one who walks in the darkness does not know where he is going.””

From the beginning of his Gospel, John has used light to describe Jesus. Light is an ancient symbol for God, and by applying it to Himself, Jesus declared His deity. Psalm 27:1 declares, “The Lord is my light and my salvation.” Jesus’ claim to be a light shining in the world teaches us that He is the One who makes God known. It is by following Christ’s light that those in the darkness are led to God.

Jesus warns that His light will soon be taken way. “The light is among you for a little while longer.” This made it urgent for anyone who would be saved to believe on Him. John 12:35 exclaims, “Walk while you have the light lest darkness overtake you. The one who walks in the darkness does not know here he is going.” This is Jesus’ warning: the Pharisees and other Jews who were opposing Him did not realize what they were bringing onto themselves.

To reject the light is to be plunged into a greater darkness. The Pharisees were themselves the greatest examples of this principle. It is clear that in the last phase of Jesus’ ministry, the Pharisees no longer seriously doubted the truth of His claims. They knew that He had given sight to the man born blind and raised dead Lazarus from the grave. But still, they rejected the light of Christ, preferring the petty darkness in which they exalted themselves. The result as that darkness overtook them and they became far more hardened to God in the end than we could have imagined at the beginning. This presents a challenge to those today who have heard and understood the gospel, but who have not yet committed themselves to Jesus in saving faith. Their encounter with the rejected Jesus will not leave them with a little light but rather with a much deeper darkness.

John 12:36, which records Jesus’ final public statement, is both wonderful and dreadful at the same time. It is wonderful because Jesus’ last words consist of an invitation to His light. “While you have the light, believe in the light, that you may become sons of light.” It says much about Jesus’ heart that He wanted His final words not to drip with the acid of condemnation but to flow with the sweet offer of God’s grace.

His departure would take the light from the world, so He leaves behind the gospel offer to become children of God by believing in His light. But even so, the aftermath of Jesus’ gospel offer is dreadful. John 12:36 says, “While you have the light, believe in the light, that you may become sons of light. When Jesus had said these things, he departed and hid himself from them.” The time comes for unbelievers when the gospel is no longer available to believe. This time might come with death, but it could also come when their hearts have come so hardened through practiced unbeliever that they are no longer able to believe. Jesus “hid himself from them”. When we realize that Jesus is the only true light the only Savior for a world lost in sin, His withdrawal from those who will not believe portends their final condemnation in eternal darkness.

The Tragedy of Darkness

Jesus’ last pleas to the Jews were straightforward. But their refusal to believe raises questions. If these Jews who alone in their world knew the Holy Scriptures and lived in God’s holy city, would not believe in Jesus then what hope is there for anyone else? Another question deals with God. If God has gone to such pains to send his only Son to offer salvation to the world, only to be so broadly rejected, does this not suggest that God has somehow failed.

Such questions are on John’s mind, so he adds a postscript to Jesus’ final sermon. John 12:37 explains, “Though he had done so many signs before them, they still did not believe in him.” This refers to Jesus’ miracles especially the great miracles of healing the man born blind and raising Lazarus. Even after this, the bottom line was the unbelief of the Jews.

What does it take to win peoples’ belief, if even this didn’t work among the Jews? To answer these questions, John turns back to the prophet Isaiah. Jesus’ earlier remarks in chapter 12 refer to Isaiah’s prophecy in Isaiah 53, and John returns to that passage. The Jews did not believe; he explains so John 12:38 says, “So that the word spoken by the prophet Isaiah might be fulfilled: “Lord, who has believed what he heard from us, and to whom has the arm of the Lord been revealed?””

Jesus had referred to this question from Isaiah 53 in explaining that he would be “lifted up” and “exalted” (Isaiah 52:13). John points out that the same passage included Isaiah’s lament that this message would be rejected. Isaiah 53:1 questions, “Who has believed what he has heard from us? And to whom has the arm of the Lord been revealed?”

This is the travesty that Jesus experienced, with both His message and His miracles rejected by almost everyone. John’s point is that the same Old Testament prophecy that foretells the cross also foretells the rejection of Jesus’ message. The Jews of Jesus’ day did not believe in Him “so that the word spoken by the prophet Isaiah might be fulfilled.” This raises some questions because it seems to say that the reason the Pharisees and other Jews rejected Jesus was that an earlier prophecy had foreordained it. This also suggests that God had predestined the Jews’ unbelief.

Many writers recoil against such a suggestion, lest God be though to compel people to sin. William Barclay objects, “It seems to say that god has ordained that certain people must not and will not believe. Now in whatever way we are going to explain this passage, we cannot believe that. We cannot believe that the God whom Jesus told us about would make it impossible for His children to believe.”[i]

Barclay suggests that we read John not to say that the Jews did not believe “so that” Isaiah’s prophecy would be fulfilled, but rather “with the result that” the prophecy was fulfilled. The unbelief of the Jews was the kind of thing that Isaiah was complaining about rather than something that Isaiah was specifying prophesying. Some stalwart Reformed commentators take the same view, including F.F. Bruce, J.C. Ryle, James Montgomery Boice, and A.W. Pink. The problem with this view is what John says (John 12:39), “Therefore they could not believe.”

In some meaningful sense it must be that, in light of Isaiah’s seven-hundred-year-prophecy, the Pharisees were not able to believe in Jesus. Their unbelief did not defeat God’s purpose; rather it achieved God’s purpose. John 12:39-40 states, “Therefore they could not believe. For again Isaiah said, “He has blinded their eyes and hardened their heart, lest they see with their eyes, and understand with their heart, and turn, and I would heal them.”” There is no way to avoid the fact that here it is God who is acting to blind and harden the people and that he does so for a reason: lest they should see, understand and turn “and I would heal them”. Isaiah 6:9-10 says, “And he said, “Go, and say to this people: ‘Keep on hearing, but do not understand; keep on seeing, but do not perceive.’ Make the heart of this people dull, and their ears heavy, and blind their eyes; lest they see with their eyes, and hear with their ears, and understand with their hearts, and turn and be healed.””

Isaiah had seen the vision of the Lord’s glory and offered his services to God. God responded by commissioning him to a preaching ministry that was designed to harden the hearts, close the ears, and blind the eyes of Israel. By explaining the unbelief to the Jews toward Jesus with this passage, John is relating Jesus’ unbelieving generation to the earlier generation of idolatry and unbelief to which God sent Isaiah to preach judgment. Now, as before, it was God’s sovereign purpose that this judgment would consist in the hardening of the people against the gospel offer of peace.

There are three ways in which we should understand God’s hardening of the Jews. First, we should realize that the Jews’ rejection of Jesus was part of God’s sovereign plan for our salvation. God purposed for the Jews to reject Jesus so that He might be crucified for our sins. This rejection involved both the will of the unbelieving Jews and the will of God. As Peter later preached in Acts 2:23, “This Jesus, delivered up according to the definite plan and foreknowledge of God, you crucified and killed by the hands of lawless men.” Peter accuses his hearers of their culpable guilt and also ascribes what happened to God’s sovereign plan.

Do we object to this? If we do, we are objecting to the very plan of God that achieved redemption through the crucifixion of Jesus. Moreover, the Jews’ rejection of the gospel brought salvation to the Gentiles, which includes most Christians today. If we object to God’s will in hardening Jesus’ Jewish hearers, we object to God’s plan for our salvation. We would do better to follow Isaiah’s example when he accepted God’s commission for his ministry of hardening: Isaiah had seen the Lord’s sovereign majesty and knew better than to pit his puny wisdom against the Lord’s holy will.

Second, John’s teaching reminds us that the gospel is a “two-edged sword” (Heb. 4:12; Rev. 1:16), giving eternal life to those who believe, but conveying judgment to those who are hardened in unbelief. This is why Jesus warned in John 12:35, “Walk while you have the light, lest darkness overtake you.” Gordon Keddie explains, “Those unwilling to believe become progressively unable to believe.”[ii] And Leon Morris writes, “They have rejected the gracious invitation of God, and it is God, none less, who has decreed that those who act in this way have their eyes blinded and their hearts hardened.”[iii]

Third, it is clear in this passage that the hardening effect of unbelief is not merely a natural cause and effect but God’s judicial response. J.C. Ryle comments, “God has given over the Jews to judicial blindness, as a punishment for their long-continued and obstinate rejection of His warnings.”[iv] This presents us with a sober reality since God has not changed over the years. People think they can wait to commit themselves to Jesus. They want a few more years to enjoy their sins, and they think that at the time of their choosing they can become Christians and start living as they know they should. But they do not realize the hardening effect of unbelief on their hearts; that it will be increasingly difficult for them to believe.

They might come to a time when it is impossible for them to believe. Moreover, since God is offended by their disdain for His Son, it is entirely possible for God to give such people over to ultimate reprobation. The time came when God gave over the Jews to a judicial hardening, so that John says in John 12:39, “Therefore they could not believe.” This explains that when God presents you with the invitation of His gospel—the gracious offer to forgive your sins and grant you eternal life through faith in Jesus Christ—that is the time when you should believe, accepting the gospel in trusting faith.

The same goes for professing believers who gain some benefit from Christianity, but who have never actually reckoned with God and surrendered their lives to Him. The longer you wait, the greater risk you take. While unbelief has the effect of hardening our hearts to the gospel, faith works in the opposite way. When our eyes accept the truth revealed in Scripture, our spiritual perceptiveness increases. When we sorrow over our sin and seek grace to repent, our hearts are made more tender and pure. When our ears are frequently attuned to the Word of God, they become sharper in hearing His voice. Through such saving faith, we turn to God and are healed. Our sins are washed away by the cleansing blood of Jesus Christ. Just as the blind man of John 9 received his sight and Lazarus was brought from death to life, our souls are restored by God’s grace until in the end we will be fully healed of every vestige of sin and corruption. All of this shows the eternal significance of how we respond to the gospel whenever it is proclaimed and offered.

2 Corinthians 6:2 states, “For he says “In a favorable time I listened to you, and in a day of salvation I have helped you.” Behold, now is the favorable time; behold, now is the day of salvation.” To put off belief in Christ is to reject Him. Jesus calls you to walk in His light and offers that in this way you will receive eternal life as a child of God. When people of their own accord and after repeated threats and promises, reject Him and spurn His messages, then and not until then He hardens them so that those who were not willing to repent may not be able to repent.

The Challenge of Faith

Part of the good news of the gospel is that God is always at work in surprising ways to bring salvation to those in darkness. This was true from the gloomy setting that John has described. He concludes the passage telling us that “among the chief rulers [i.e. Pharisees and Sadducees] also many believed on him” in John 12:42. It is hard to imagine a more difficult ministry setting than that of the Pharisees and Sadducees who were seeking to put Jesus to death.

When Jesus offered them salvation one last time, even among this hostile group, there were some who began to see His light. But there was a problem with these new converts. John says that while they had believed in Jesus, “for fear of the Pharisees they did not confess it, so that they would not be put out of the synagogue.” This reminds us that there is a price to following Jesus. Jesus offers a free salvation, but it comes with the possibility of the world’s rejection. These new believers were reluctant to be cast out of Jewish society, which was what expulsion from the synagogue entailed. But Christ demands that His followers not be secret disciples; sooner rather than later, a true believer must go public with his faith in Jesus Christ; regardless of the cost.

Mark 8:38 proclaims, “For whoever is ashamed of me and of my words in this adulterous and sinful generation, of him will the Son of Man also be ashamed when he comes in the glory of his Father with the holy angels.” John tells us that these men who believed remained silent. John 12:43 says, “For they loved the glory that comes from man more than the glory that comes from God.” This is a particular temptation to those who are high in the eye of the world. Many if not most Christians struggle with these same temptations. This is one of the reasons why we are tempted to blend in with the world in our manner of living. We fear to be ostracized if we live openly and boldly as followers of Christ. We are reluctant to speak to people about the only Savior who can redeem their souls.

Final Thoughts

What will break this spell of our fear of man and love of the world? The answer is found in the word that appears in verses 41 and 43: glory. These cowardly Pharisees were afraid to admit their belief in Jesus because they were enthralled by the glory of this world. But in contrast, Isaiah committed himself to the Lord, “because he saw his [Jesus’] glory” John 12:41 says.

If we go back to Isaiah 6, we read that he, “…saw the Lord sitting upon a throne, high and lifted up; and the train of his robe filled the temple.” (Isaiah 6:1). It was Jesus that He saw in a seat of ultimate sovereignty, high and majestic over every power and authority. He saw that Jesus’ robe filled the temple so that there was no room for any other sovereign in His kingdom. Isaiah also saw holy angels, the seraphim, and they were singing in rapturous praise. Isaiah 6:3-4 states, “And one called to another and said: “Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory! And the foundations of the thresholds shook at the voice of him who called, and the house was filled with smoke.” Isaiah saw the weightiness of Christ, the awesomeness of Christ, the holiness of Christ, and the consuming fire that burns in the heart of our Lord.

As a result Isaiah no longer feared the world or stood in thrall to its tarnished glory. He would stand against the world with Jesus and speak to the world for Jesus. If the same is not true of us, then the logical explanation is that we have not seen what Isaiah saw. We are more concerned with our lifestyle, our comfort, and with getting by in the unholy world. This is why we are more interested in practical matters and consider theology boring and irrelevant. This is why we fear the world and love its glory. This shows that our greatest need is to see the glory of Christ, as Isaiah did. J.C. Ryle comments, “The expulsive power of a new principle, making us see God, Christ, heaven, hell, judgment, eternity, as realities is the grand secret of getting the victory over the fear of man.”

Isaiah received his vision of Christ by direct revelation, as the Lord revealed His glory to the grieving prophet in the Temple. How, then, are we to see the glory of Christ? The answer is that for Christians today, the glory of Christ is found shining through the Word of God. This is what Peter emphasized in his second letter. He admitted that he had the privilege of witness miracles and seeing visible displays of Christ’s glory. 2nd Peter 1:19 says, “And we have the prophetic word more fully confirmed, to which you will do well to pay attention as to a lamp shining in a dark place, until the day dawns and the morning star rises in your hearts.”

This is what the two disciples discovered on the Emmaus road. Jesus appeared to them on the day of His resurrection, yet His chief display of glory was in explaining the Bible. Luke 24:32, “They said to each other, “Did not our hearts burn within us while he talked to us on the road, while he opened to us the Scriptures?”” The Lord has given to His Word the power to convey the glory of Christ to our souls. When the Bible becomes that for us the revelation of divine glory to our faith then we will no longer have to worry about the danger of our hearts’ becoming blackened, we will cease to fear what man might do, and the spell of worldly glory will be broken. For Christ will be high and exalted on the throne of our hearts and the train of His robe will fill the temple of our souls.

[i] William Barclay, the Gospel of John, 2 vols. (Philadelphia: Westminster, 1975), 2:153).

[ii] Gordon J. Keddie, A Study Commentary on John, 2 vols. (Darlington, UK: Evangelical Press, 2001, 1:485.

[iii] Leon Morris, Reflections on the Gospel of John (Peabody, MA: Hendrickson, 1986), 460.

[iv] J.C. Ryle, Expository Thoughts on the Gospels: John, 3 vols. (Edinburgh: Banner of Truth, 1999), 2:416.