Our series so far has tried to show the biblical evidence that Jesus’s death is substitutionary, Jesus dying in our place so that we don’t have to. https://jotsandscribbles.blog/2025/08/23/is-jesus-death-substitutionary/Then we saw evidence that Jesus’ death is him taking the just penalty for our sin in our place so that we receive the blessing he has earned https://jotsandscribbles.blog/2025/08/24/is-jesus-death-penal/. Thirdly, we saw that on the cross Jesus took God’s wrath at our sin so that we can draw near to God without fear of his anger https://jotsandscribbles.blog/2025/08/25/is-god-angry-at-jesus-on-the-cross/.
In the next two posts, I want to briefly think about why evangelicals have generally found this understanding (penal substitution) of Christ’s work on the cross so helpful and made it so central.
The first reason is the one we’ll cover in this post. Penal Substitution shows particularly clearly how the cross upholds all of God’s character as he rescues us. The dilemma it resolves can be seen if we ask: Why can’t God just forgive sins without the cross?
On one level, this is a very reasonable objection. We praise human beings who forgive wrong done against them without demanding justice. And God is omnipotent, so why can’t he just declare sins forgiven without Jesus having to go through the agony of the cross?
But the problem is that our human forgiveness is virtuous because we are leaving justice to God. But if God, the Judge of all the world, does not punish wickedness, then there is no ultimate justice. If God does not punish sin then he cannot be perfectly just. Justice is punishing wickedness and rewarding righteousness. God has to be perfectly just in character.
And yet God’s character is also to be compassionate and merciful. Mercy is defined as not giving people the just punishment they deserve. An example would be David, who adulterously slept with Bathsheba, and then murdered her husband Uriah. Under the law of God David deserves death. But God forgives David. On one level we like that- if we see ourselves as David, if we know we have sinned, we like a God who forgives. But when someone has sinned against us, we don’t like it. The Psalms are full of appeals for justice, for God to punish the wicked who are oppressing God’s people. Uriah could rightly cry out to God- you are unjust to forgive David- he is a murderer and an adulterer and deserves death and your anger.
Without a way for sin to be transferred to a substitute and punished, the options seem to be that God’s justice means he can’t forgive us till we pay for our sins, or his mercy means he doesn’t punish sins, which means God is unjust. I think this dilemma is implicit in Islam where God’s 99 names include All just and All merciful- but with no explanation of how God can be both.
But penal substitution solves this. God is just- he punishes every human sin fully. God is compassionate- he takes the punishment for the sin on himself so he can forgive sinners. On the cross, by this exchange, by this self substitution, God is able to demonstrate perfect commitment to justice for human sin and perfect compassion and mercy for human sinners.
Nor is this something theologians had to laboriously make up. The law court imagery, and the challenge for how God can be just and forgiving comes from Romans 3. 25 God presented Christ as a sacrifice of atonement, through the shedding of his blood – to be received by faith. He did this to demonstrate his righteousness, because in his forbearance he had left the sins committed beforehand unpunished 26 – he did it to demonstrate his righteousness at the present time, so as to be just and the one who justifies those who have faith in Jesus. Romans 3:25-26 Only by the Jesus dying taking the punishment for human sin at the cross does God’s forgiveness of David not look unrighteous and unjust. Only by the penal substitutionary death of Jesus can God be just and the one who justifies sinners who trust Jesus.
By focusing on the character of God question, we can see why God can’t just solve the sin problem by a new decree. We can see why the cross is the only way God can save sinful people. This can then act as a key to unlock other perspectives on the cross like Christus Victor, Jesus defeating the devil. In a battle of power, God can defeat Satan at any time. God is creator, Satan is only a mighty angel, so God is on a different level of power. Yet God does not destroy Satan because Satan has hostages- us. By our sin we have joined Satan’s kingdom. By our sin, Satan can come into God’s presence with accusations and the accusations are true (Job 1). So the problem is not lack of divine power, but removing people from Satan’s power, and specifically the power that he gains because his accusations of humans sinning are true. The cross defeats Satan by enabling sin to be forgiven justly, by a great exchange. So by the penal substitutionary death of Jesus on the cross Satan is thrown out of heaven.
(10 Then I heard a loud voice in heaven say:
‘Now have come the salvation and the power
and the kingdom of our God,
and the authority of his Messiah.
For the accuser of our brothers and sisters,
who accuses them before our God day and night,
has been hurled down.
11 They triumphed over him
by the blood of the Lamb
and by the word of their testimony;
they did not love their lives so much
as to shrink from death. Revelation 12:10-11)
None of this is to say no other perspectives on the cross deal with God’s character, or explain why the cross is necessary for salvation. I think a holiness lens might do something similar to the justice lens in terms of highlighting the need for a resolution between aspects of God’s character and his plan to rescue sinful people. A therapeutic lens might highlight the challenge of getting the divine life into finite and spiritually dead humans, and how the cross and resurrection are God’s amazing way to do this.
But penal substitutionary atonement, shown clearly in the Bible, has proven a helpfully clear way to think about how God can maintain his character while forgiving us. It shows how God himself resolves the divine dilemma of justice for human sin and mercy for human sinners.
I’ll finish with a quote from John Stott’s Cross of Christ.
We strongly reject, therefore, every explanation of the death of Christ which does not have at its centre the principle of ‘satisfaction through substitution’, indeed divine self-satisfaction through divine self-substitution.
The cross was not:
a commercial bargain with the devil, let alone one which tricked and trapped him;
nor an exact equivalent, a quid pro quo to satisfy a code of honour or technical point of law;
nor a compulsory submission by God to some moral authority above him from which he could not otherwise escape;
nor a punishment of a meek Christ by a harsh and punitive Father;
nor a procurement of salvation by a loving Christ from a mean and reluctant Father; nor an action of the Father which bypassed Christ as Mediator.
Instead, the righteous, loving Father humbled himself to become in and through his only Son flesh, sin and a curse for us, in order to redeem us without compromising his own character.
The theological words ‘satisfaction’ and ‘substitution’ need to be carefully defined and safeguarded, but they cannot in any circumstance be given up. The biblical gospel of atonement is of God satisfying himself by substituting himself for us.
John Stott, The Cross of Christ (Downers Grove, IL: InterVarsity Press, 1986), 159-160.
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