Some years ago at our church we got our trainees to read J. I. Packer’s classic essay “What did the Cross Achieve?” In it, the great British theologian sets out a careful, nuanced, and compelling case for the penal substitutionary nature of Christ’s work on the cross. I was excited for them to read it.

Packer carefully defended a position they had no idea needed defending … like the existence of gravity.

They were underwhelmed. They did not find any fault with the writing, or the exegesis, or the theology as such. Rather, the trainees were perplexed because, for them, it was hard to make sense of what he was arguing against. Christ died in our place to take the penalty for our sins—who’s on the other side of this issue? Packer carefully defended a position they had no idea needed defending. It was like reading an earnest essay defending the existence of gravity.

Penal substitutionary atonement is a bit like that. In the academy and among Christian leaders the idea is controversial, contentious, and occasionally used as a tribal boundary marker. Denominations and ministries have split over the issue. Vast quantities of ink have been enlisted in its defence, or to bring about its defeat. Others have set out to recuse it from some of its more clumsy presentations. Meanwhile, as these theological armies clash by night, the average Christian can be found cheerfully belting out the truth that “on the cross, as Jesus died, the wrath of God was satisfied” blissfully unaware of all the fuss.

Christ died in our place for our sins: Penal Substitutionary Atonement

The idea of penal substitutionary atonement is, as the name suggests, the claim that Christ’s death paid a penalty (“penal”). As Christ did not deserve a penalty, he was paying it for others (“substitutionary”). And, the result of Christ’s paying this price for others is that we are now forgiven (“atonement”).

The idea of a “penalty” takes us into the realm of the law-court, the world of crime and punishment. Before the judge, the guilty party is dealt a penalty for their misdeeds, whether that be a fine, a prison sentence, or (depending on the jurisdiction) the death penalty.

Does our sin warrant a penalty? The answer (it seems almost too obvious to even have to answer) is ”yes”. God is the judge of all the earth. He will not leave the guilt unpunished.

We are speaking of a judicial rather than natural penalty … it means more than ‘cause-and-effect in a moral universe’.

Notice that the law court image means we are speaking of a judicial rather than natural penalty. A natural penalty is the consequence baked into the act itself. Abuse of alcohol leads to bad health outcomes, reckless spending leads to poverty, unkindness leads to a diminished social life. But in this context the penalty means more than “cause-and-effect in a moral universe”. It specifically refers to the idea that God our judge applies a judicial penalty to our sins.

For punishment to be just, it must also be proportional. The practice in some nations of removing a man’s hand for stealing might be effective, but it is also unjust. Stealing is a sin, to be sure. But losing your hand for the rest of your life is wildly out of proportion to the sin itself.

What is the just punishment for our rebellion against God? The Bible’s answer is death. God gave us life. To take his gift and reject the giver is treason. It is a capital offence. “The wages of sin is death” as Paul says in Romans 6.

The second half of this doctrine states that Christ himself substitutes for us. He takes our penalty.

The idea of substitution is admittedly wide ranging. Sometimes, as on a sports team, substitution has a one-to-one correspondence. Someone comes off the field and someone else steps in and takes their place. Other times, substitution has a more representative character. The prime minister (or president or monarch) represents us as a nation. And representation has an aspect of substitution. The one who stands for us stands where we would otherwise have needed to stand, and so substitutes for us. And the one who stands for us must be one of us. Substitution has also a solitary aspect, like the priest who walks from the people into the holy of holies.

All of this is in play here. But specifically, when we speak of penal substitutionary atonement, we are highlighting the “in our place” aspect of substitution. The penalty was due to us. It fell on Christ. And this is because he stood where we otherwise should have been, and received what we otherwise should have received.

The penalty was due to us. It fell on Christ … he stood where we otherwise should have been, and received what we otherwise should have received.

By this means our sins are atoned. Because Christ substituted as our penalty, we are now able to stand before God guiltless. We have no case to answer, no penalty to pay no punishment to await. This is what is meant by penal substitutionary atonement.


Depending on your background, the statement above may still leave you scratching your head, wondering what possible objection it could raise? Isn’t everything we’ve just said more or less what the Bible says? Let’s consider the nature of the objections sometimes raised.

Some of the objections come from unbelief, or alternative beliefs. For example:

  • Islam sees no atonement in the death of Jesus because it says that Jesus did not die;
  • Atheists object because there is no God who needs to be propitiated;
  • Liberal or progressive Christians might accept this is what the Bible says, but relegate it to an early phase of human reflection on the cross from which we have since advanced.

These are all good topics for discussion in another context, but they are not our focus here. Rather, I want to focus on three questions that arise, as it were, from within the logic of penal substitution itself. These objections, if answered, will serve us in believing more intelligently and faithfully:

  1. Why doesn’t God just forgive?
  2. Is substitution just?
  3. Is penal substitution rational?

1. Why doesn’t God just forgive?

First, why must a penalty be paid at all? God seems to require us to just forgive others. Why doesn’t he do the same?

The answer is in the character of God and the nature of forgiveness. God is just. He cannot wink at sin. To forgive would be to leave sin unpunished, and so to enthrone evil. In his searching book Exclusion and Embrace, Miroslav Volf explores the question of violence with reference to his own background in war-torn Croatia. In the face of manifest evil, such as genocide, a God who simple forgave would be a God who condoned evil. In Volf’s words:

Absolute hospitality would in no way amount to the absence of violence. To the contrary, it would enthrone violence precisely under the guise of nonviolence because it would leave the violators unchanged and the consequences of violence unremedied.

The choices are stark: either God ignores the cries of the oppressed for justice and so condones the perpetrators. Or he punishes evil and in doing so closes the door on forgiveness. The genius of the cross is that it achieves both. In it, God is both “just and the one who justifies those who have faith in Christ” (Romans 3:26). In the cross, God both condemns evil and embraces sinners.

The idea that forgiveness is about simply ‘letting it go’ could only be believed by people who’ve never had to forgive anything.

The objection also entails a false assumption—namely that forgiveness is costless. It never is. The idea that forgiveness is about simply “letting it go” could only be believed by people who’ve never had to forgive anything significant. The truth is whenever we forgive someone, the cost of sin doesn’t just disappear. It gets borne by the one doing the forgiving.

A simple example. If you borrow $1000 from me and cannot replay it, I can choose to forgive you. But in the act of forgiveness, the $1000 doesn’t now magically appear back in my bank account. If I forgive you the debt, “forgiveness” is shorthand for “I will bear the cost for the wrong you did”. Forgiveness is always like that. The cross, in this sense, is simply the inner logic of forgiveness writ large.

2. Is substitution just?

How can it be okay—morally, ethically, legally—for the innocent to be punished for the guilty?

At this point I freely concede that we can be our own worst enemies. We can present the substitution of Jesus in ways that create more problems than they solve.

Take for example the once popular illustration of the railway controller who sees a train heading unstoppable for a crowded platform, guaranteeing the death of all on it. The only hope is to divert the train to the other railway line. But in that moment the controller sees that his son, his beloved son, is playing on the line. What can he do? He chooses to divert the train, thus killing his son but saving the lives of all the others.

As an illustration it gets an A+ for emotional impact, but (I’m afraid) a D- for theological accuracy. The whole thing, frankly, is a hot-mess. As a picture of substitution, it places the son in the place of an innocent and unaware victim, and the father as himself a hapless victim of circumstance. Now add to this picture of substitution the element of punishment, and the trouble only compounds. Let’s move to a courtroom metaphor, with a judge offering to send his son to jail in place of a murderer. How is that in any way fair?

The problem, I submit, is in the simplistic nature of the metaphors. If God is a singular being, choosing random people to bear the punishment for other people’s wrong, we’d have a problem. Even if God is depicted as a human father choosing to punish his innocent but willing son, we’re still not out of the woods. As Psalm 49 puts it “No one can redeem the life of another or give to God a ransom for them.”

The solution takes us into the heart of the trinitarian nature of God. “God was in Christ reconciling the world to himself”. Jesus, the son of God, was not a third party. In the trinitarian life of God, God was taking the weight of sin onto himself. The atonement is, in the phrase of John Stott, ultimately the “self-sacrifice of God”.

3. Finally, is penal substitution rational?

The objection here is to stand back and say: “What are we actually saying?” Are we really arguing that guilt and punishment are these things in the universe that can be moved about from one person to another? What magical view of reality is this, where a random death on a cross two-thousand years ago removes the guilt I incur for a sin I did last Tuesday?

Fair question. My answer, for what it’s worth, is to appeal to the limits of our language relative to the mystery of our subject, namely God. What I mean is this: Penal substitution is rational (it makes sense), but it is not rationalistic. It does not, nor does it pretend to, dot every “i” and cross every “t” in explaining the ways of God. We are talking about ultimate reality here. And to do so we stretch human language to near breaking point. Sin has a penalty. Christ is our substitute. He brings our atonement. That much we can comprehend. But as to the precise “mechanics” (and what an awful word to use in this context) of how God achieves my forgiveness and reconciles the world to himself in Christ, what would I know!? As Wesley says in his great hymn “Tis mystery all, the immortal dies”. As J. I. Packer puts it in his great essay:

How was it possible for him to bear their penalty they do not claim to know, any more than they know how it was possible for him to be made man: but that he bore it is the certainty on which all their hope rests. 

Certainty that our sins are forgiven, and intellectual modesty about understanding precisely how—this is where penal substitutionary atonement places us. And it’s a good place to be.

Good News for Sinners

The doctrine of penal substitutionary atonement has caused headaches for the church’s logicians. It’s never caused much trouble to the church’s poets. It may have fallen out of textbooks at key points, but it’s never far from the church’s hymns. It’s a truth perhaps better sung than said. The truth that Christ in his death took the penalty for my sins is something that fills out hearts even as it exercises our minds.

The bliss, oh the bliss of this glorious thought,
my sin not in part by the whole,
Is paid on the cross and I bear it no more,
Praise the Lord Oh my Soul.

This is an excerpt from Rory’s forthcoming book on the cross, Forgiven Forever. See another extract on the topic of shame here.