"How is it," they say, "that You say that the Son of Man must be lifted up?" You see, they understood much even from the Lord's parabolic sayings — for example, they understood that by the words "to be lifted up" He speaks of the Cross. Yes, they truly understood much, but out of their evil will they feigned ignorance. Note, then, what they say: "How do You say that the Son of Man must be lifted up? Who is this Son of Man?" Their speech is full of malice. They speak as if to say: "Although we do not know of whom You speak or who the Son of Man is, we nevertheless clearly understand the truth that whoever is lifted up, whoever he may be, is not the Christ — this is incompatible, for the Scriptures say that Christ is immortal."
Jn. 12:35. Then Jesus said to them: Yet a little while the light is with you; walk while you have the light, lest darkness overtake you: for he who walks in darkness does not know where he is going.
What then does the Lord say? Stopping their mouths and showing that His sufferings in no way prevent Him from abiding forever, He says: "Yet a little while the Light is in you." By Light He referred to Himself. Just as the light of the sun does not completely disappear, but is hidden and shines forth again, so too My death is not destruction, but a setting and a departure, and through the resurrection I shall shine forth again. And since the sufferings in no way prevent Me from being eternal, and the Scriptures testify concerning Christ that He is eternal, then I am truly Christ, even though I shall endure sufferings. For I am the Light; I shall set and rise again.
Jn. 12:36. While you have the Light, believe in the Light, so that you may become sons of light.
So then, while the Light is with you, walk, that is, believe in Me. What time is He speaking of here? He speaks of the time before the sufferings, or of the time after the sufferings, or of both together. So then, He says, walk and believe in Me both before My crucifixion and after it. He indicates this by the words "while the Light is with you," that is, while you can believe in Me; and to believe in Me, who am the Light, you can both before the sufferings and after them. But whoever walks in unbelief does not know where he is going. For whatever the Jews do now, they nevertheless do not know what they are doing, but walk as if in darkness; they think they are going on the straight path, but everything turns out the opposite for them, when they observe the Sabbath and circumcision. But those who have believed do not act this way. They walk in the light, doing everything that pertains to salvation. For they escaped the shadows of the law and the darkness of riddles, and came to the light that had been hidden in them but has now shone forth, and became sons of the Light, that is, of Christ. "That you may become," He says, "sons of the Light," that is, My sons. Although the Evangelist at the beginning of the Gospel says that some were born of God (John 1:13), here he calls them sons of the Light, that is, of Christ. Let Arius and Eunomius be put to shame. For here too it is shown that the Father and the Son have one operation.
Jn. 12:36. He said this, and Jesus departed and hid Himself from them.
Why did the Lord hide from them? They had not now taken up stones against Him, nor spoken any blasphemy, as before. Why then did He hide? Although they said nothing, yet penetrating into their hearts, He saw that their fury was increasing. To subdue their hatred, He hides Himself.
Jn. 12:37. Although He had done so many miracles before them, they did not believe in Him,
That they did not believe but were vexed, the Evangelist himself indicated when he said, "Though He had done so many miracles, they did not believe in Him." And of course it is a matter of no small malice not to believe so many miracles. "So many," he says, "miracles about which he [the Evangelist] kept silent."
So. Jesus hid Himself in order to calm their malice, and at the same time in order to give them time and tranquility so that, having calmed down, they might consider His words and deeds. For in that case, if they had wished, they could have come to an understanding of His dignity — His Divinity. Although He knew their unbelief in advance, nevertheless, what depended on Himself, He did and permitted, giving them, as has been said, time for consideration.
Jn. 12:38. That the word of Isaiah the prophet might be fulfilled:
In the words "they did not believe in Him, that the word of Isaiah might be fulfilled," what is expressed is not the cause, but the event. For they did not disbelieve in Christ because Isaiah had foretold it about them, but the prophet foretold it about them because they would not believe.
Jn. 12:38. Lord! Who has believed what they heard from us?
Let us also examine the words of Isaiah: "Lord, who has believed our report?" (Isa. 53:1). This means the same as "no one believed." For the word "who" is used in many places of Scripture in place of "no one." The prophet said this as if speaking in the person of Christ. Christ speaks thus, as it were, to the Father: "Lord, who has believed our report?" — that is, no one has believed Our word and My preaching, which He called "report." For He says: "What I have heard from My Father, that I speak" (John 8:26).
Jn. 12:38. And to whom has the arm of the Lord been revealed?
"And to whom has the arm of the Lord been revealed?" — that is, the mighty working of miracles, which He called "the arm," was not revealed to any of the senseless Jews, but they slander Me even when I perform so many miracles.
Jn. 12:39. Therefore they could not believe, because, as Isaiah said again,
The same thought is expressed in the words "therefore they could not believe, because Isaiah said again of them." By all this He wants to confirm that Scripture is not false and that the prophecy of Isaiah was fulfilled exactly as he had foretold.
Lest anyone should begin to speak and wonder why Christ came at all if He knew that the Jews would not believe in Him, the Evangelist for this reason brings forward the prophets who foretold this. Christ, although He knew of their unbelief, nevertheless came so that they would have no excuse for their sin and could not say that they would have believed if He had come.
The words "they could not believe" mean the same as "they would not." For an evil and crafty man, so long as he remains such, that is, chooses evil, cannot believe.
Jn. 12:40. This people has blinded their eyes and hardened their heart, lest they see with their eyes and understand with their heart, and turn, so that I should heal them (Is. 6:10).
When you hear that God blinded their eyes and hardened their heart, do not think that He simply makes some good and others evil (away with such a thought!), but by the complete blinding understand the abandonment by God.
I will explain with an example. Suppose someone is moderate in wickedness. God, it seems, is with him, because there is hope that such a person will turn back. But when a person plunges into the depths of wickedness, then God abandons him on account of his evil will. Of a person who has been deprived of the Divine light and walks in the darkness of sin, it is said that he walks as one who is blind; the absence of the Divine word, which softens the hearts of those who receive it, is called hardening of the heart. Already blinded is the one who completely refuses to receive the ray of Divine light, and hardened is the one who does not wish to hear the teaching that softens the heart, and God's withdrawal completely blinds and darkens him. So when you hear that God blinds, understand it in this way: He blinds because He is not present. For if God were present with a person, the person would not have become blind. If the sun were there, there would be no darkness. But now the sun produces night. In what way? By setting. So too God makes people blind by withdrawing from them. And He withdraws from them on account of their wickedness, and from that point on they, like blind men, sin irretrievably and fall incorrigibly.
Jn. 12:41. Isaiah said these things when he saw His glory and spoke about Him.
"These things said Isaiah, when he saw His glory." Whose? The Son's. Although the prophet, judging by the connection of the speech, seems to have seen the glory of the Father, the evangelist says here that Isaiah saw the glory of the Son, and the apostle Paul says that he saw the glory of the Spirit (Acts 28:25). Truly the glory of the Holy Trinity—Father, Son, and Holy Spirit—is one.