Knowing the Great Exchange
Sunday Seminary—9
Know What You Believe. Believe What You Know.
In your sins, you are helpless to save yourself. It’s like you’ve murdered your neighbor, been tried, found guilty, sentenced to death, and locked away in a federal maximum-security prison—living on borrowed time. There’s no helping yourself.
But God!
Our merciful God sent his Son to assume the very human nature in which the disobedience had been committed (Belgic Confession, art. 20). Yet because God is also just, he sent his Son so that in that same human nature he might bear the punishment for sin by his most bitter passion and death. Mercy for me; justice for Jesus.
This is what theologians call the great exchange. Paul says it this way:
For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God (2 Cor. 5:21).
Article 20 summarizes it beautifully:
God made known his justice toward his Son,
who was charged with our sin,
and he poured out his goodness and mercy on us,
who are guilty and worthy of damnation,
giving to us his Son to die by a most perfect love,
and raising him to life for our justification,
in order that by him we might have immortality and eternal life.
The Son was born that we might be born again.
He was charged with sin that we might be acquitted.
He died that we might live.
He endured justice that we might experience mercy.
What a God! What a Savior! What a gospel! Let’s continue our Sunday Seminary with knowing the great exchange.
The Sinless Son Made Sin
On one side of this great exchange stands the sinless Son made sin: “He made Him who knew no sin to be sin for us” (KJV).
As God, the Son is perfectly holy. As the incarnate Son, Jesus was conceived by the Holy Spirit and lived in perfect obedience to God’s law. Yet the Father “made” him—reckoned him—to be sin for us. He took upon himself our guilt and punishment.
In human courts, such an exchange would make no sense. But in God’s court of mercy, Christ stood in our place. He presented himself before the Father to appease divine wrath by offering himself on the cross and pouring out his precious blood for our cleansing.
Isaiah said, “The chastisement of our peace was upon him, and with his wounds we are healed.” He was “led as a lamb to the slaughter,” “numbered among the transgressors,” and “the just for the unjust.” In both body and soul, he bore the horror of divine judgment—his sweat falling like great drops of blood as he cried, “My God, my God, why have you forsaken me?”
The Sinful Made Sons
On the other side of this great exchange stand the sinful made sons: “That we might become the righteousness of God in him.”
We, the unrighteous and disobedient, are now reckoned righteous in Christ. His obedience is credited to us; his record becomes ours. You walk free from death row with a clean slate.
Sinner, trust in the sinless Savior! Let him take your sin and give you his righteousness. When you do, at least two applications follow:
Rely more on Christ and less on yourself. As Paul said, “I determined to know nothing among you except Jesus Christ and him crucified.” Everything else is “rubbish” compared to knowing him.
Rest in Christ alone as your Mediator. We find all comfort in his wounds. There’s no need to invent other means to reconcile ourselves with God. His one sacrifice, once made, perfects believers forever.
This is why the angel said, “You shall call his name Jesus”—that is, Savior—“for he will save his people from their sins.”
Heart of Christ and Heartbeat of the Christian
The great exchange is the great reversal—Christ took your sin and gave you his righteousness. In his death you died; in his life you live. This is the heart of Christ and his gospel and the heartbeat of the Christian.