We're about to begin our third and final day of the 2014 Pastors Conference here in Minneapolis and it's been a wonderful conference, so thank you for your prayers over the last few days. Today's APJ question is about the Gospel and it comes from Melody in Ithaca, New York. She writes, "Pastor John, how can it be just to punish someone innocent in the place of someone guilty?

I've heard it said that the cross was unfair, but I can't bring myself to say that God would do anything that's unfair." No, we surely cannot say that God would do anything unfair and that is not a small question, it's a biblical question. Justice does demand that punishment happen to the one who committed the sin.

Deuteronomy 24, 16, "Fathers shall not be put to death for their children, nor shall children be put to death because of their fathers. Each one shall be put to death for his own sin." Period. That's why the cross is an offense to the Jews and should it be? That's the question.

Is it just? Does it break God's law? Did God break God's law in presuming to cause Christ to be a substitute? And it's the very heart of the Gospel, so you can't ask a question any more essential than this because 1 Corinthians 15, 3 says, "Christ died for our sins." 1 Peter 3, 18, "Christ suffered once for all, the righteous for the unrighteous." Just as blunt as it could be that this seems wrong.

How can a righteous person die in place of an unrighteous person? He didn't do the sin. Or Isaiah 53, "We esteemed him stricken, smitten by God and afflicted. He was pierced for our transgressions. He was crushed for our iniquities." So her question is massively central, massively important. How is it just?

And over the years of my reflecting about this, two different ways of answering the question have seemed helpful. I'll give you both of them as quick as I can. The first one is the doctrine of union with Christ. God has the right and the ability to constitute, to make a union between Adam and humanity so that when Adam fell, we all fell in him, so that the punishment that came on Adam also came on us because we were in union with Adam.

And God can do that. He can constitute a union. I would recommend Ever's book on Original Sin. That was the most helpful of anything I've ever read on how God does that. Because of one man's trespass, death reigned through that one man on everyone. As one trespass led to condemnation for all, Romans 5, 18.

And the same principle is operating when Christ, the new Adam, dies for his people, the new humanity. "For as by one man's obedience the many were made sinners, so by one man's obedience the many will be made righteous." So the reason Christ can bear our punishment and become our righteousness is that we are in him.

There's a union that God constituted between us and Christ that makes his death our death. 2 Corinthians 5, 21. "For our sake God made him to be sin who knew no sin, so that in him, in union with him, we might become the righteousness of God." So this union does not exist between a son and a father.

So it would be unjust for a father to be punished for his son, like Deuteronomy says. God established a union between Christ and his people, and that's unique. And only God can create that union, and that establishes Christ as our representative in such a full way that it's virtually true that we are being punished in him.

That's the first way to think about it. Here's the second way, and this comes from Anselm. And I think Anselm's book, "Why the God-Man," is massively important. There are two main reasons why a mother cannot justly go to jail and serve the rest of her son's life sentence while the son goes free.

Number one, the crime against the state, the crime was against the state, and the mother's willingness to go to jail does not repair the injury done to the rights and the honor of the state. It's a sign of compassion for her son. The worth of the criminal to her, not the worth of the honor of the law, is her main concern.

But with Christ, it is different. Christ did come to vindicate the righteousness of God, Romans 3.25, and he did come to repair the glory that was done to his father in our sin, John 12.27, "For this purpose I have come. Father, glorify your name." So that's the first difference.

Second difference is this mother's desire for her son to go free provides no guarantee that this will not release a criminal onto the community and make him law-abiding. There's nothing certain about that at all, and it looks like we're playing fast and loose with whether criminals go free. That's not the case with Christ, and this is unique to Christ.

Everyone whom he saves by dying for them, he sanctifies. That's the point of Romans 6. When he died for us, we died in him. Our old self was killed, was dead, and therefore substitution is always transformation. Substance not true in ordinary jurisprudence. So those are my two ways of approaching this problem.

The one is union with Christ, and the other is the difference, the deep differences between the way Christ provides a substitute for us and the way, say, a typical mom would try to take the place of her son in prison. Yeah, that's very good, Pastor John. And this conversation reminds me of our recent podcast, which was titled "Muslims vs.

Christians on the Sovereignty of God," where you talked about God's wrath, justice, and sovereignty in contrast to Islam. That was episode number 234 in the Ask Pastor John archive. Tomorrow we'll talk about what you, Pastor John, believe to be the single most important verse in all of the Bible.

Hmm, I'm very curious about which verse you're going to choose. I'm your host, Tony Reinke. Thanks for listening. 1. What is the single most important verse in the Bible? 2. Which verse is the single most important verse in the Bible? 3. Which verse is the single most important verse in the Bible?

4. Which verse is the single most important verse in the Bible? 5. Which verse is the single most important verse in the Bible? 6. Which verse is the single most important verse in the Bible? 7. Which verse is the single most important verse in the Bible? 8. Which verse is the single most important verse in the Bible?

9. Which verse is the single most important verse in the Bible?