Is Penal Substitution Fair?

Before moving on to verse 4 of Romans 8, let’s consider one more question that arises from considering verse 3:

"For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh,"

What a wonderful statement of our salvation! God condemned our sin; He exacted the full payment for our sin, and He did this through sending His Son in the likeness of sinful flesh. Jesus Himself had no sin, but on the cross He bore our sin in His own flesh. That is what Paul means in verse 3. God condemned our sin in Jesus’ flesh; that is why there is therefore now no condemnation for those who are in Christ Jesus (verse 1).

Is this fair? If I am found guilty of murder and sentenced to the death penalty, someone else cannot come along and say, “In love, I will suffer the penalty of death, so that Larry can go free.” It may be a very loving act for someone to offer to do this, but it is not fair. It is unrighteous. Another person cannot be punished for the crime of another. So how can God be just in punishing another person, even a sinlessly perfect, willing person, for the sins of another person?

In a wonderful book on the doctrine of penal substitution (i.e., the teaching that Jesus suffered the punishment [=penal] for sin in our place [=substitution]) called Pierced for Our Transgressions, authors Steve Jeffery, Michael Ovey and Andrew Sach suggest that the key to unlocking that mystery is the doctrine of union with Christ (which we looked at in this blog post). They refer to an illustration used by Martin Luther about a marriage between two people, one of them a debtor. For instance, when I entered into marriage covenant with Michelle, by virtue of my legal union with her, her college debt was counted to me. I knew that in marrying her, I was bringing debt upon myself.

It’s not a perfect analogy, but in a similar way, our sin has accrued for us a “moral debt” before God. That debt is death (Romans 6:23). Jesus so loved His people that He willingly came from heaven to earth in flesh and blood and united Himself with us in such a way that our guilt before the Almighty was counted (imputed) to Him, and He bore all that guilt in our place by His death on the Cross. In union with us, Jesus paid the wages of sin in our behalf, and this does not compromise God’s justice because we are in union with Jesus.

Union with Christ explains how an innocent person can be justly punished for others’ sins; in union with Him, our sins become His, and are then condemned in His death on the cross. This also explains how a guilty person can be justly acquitted; believers are one with the sinless Lord Jesus, so that His perfect record of righteousness can be imputed to us. In another of his letters, Paul captures both sides of this exchange:

"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 Corinthians 5:21).

The doctrines of penal substitution and union with Christ are weighty, complex doctrines. Analogies like the one presented here can only give us a hint at the glorious wonders of our salvation. But hopefully these considerations add depth and understanding to the precious truth we sing often at our Sunday gatherings:

Bearing shame and scoffing rude,
In my place condemned He stood;
Sealed my pardon with His blood.
Hallelujah! What a Savior!