Why can’t God forgive sin without the cross?

As I’ve argued on this blog many times before, I’m a proponent of the doctrine of penal substitution, or penal substitutionary atonement (PSA). I believe that it isn’t merely one way of understanding what God accomplished through his Son Jesus Christ on the cross—as if we can choose among several equally compelling alternatives: it’s the main way of understanding the Atonement.

In advocating for PSA, I’m standing on the shoulders not only of the Protestant Reformers but also Jacob Arminius, John Wesley, and most of the classic Methodist theologians who followed in their wake.

But these are only men, of course. More than anything, I believe PSA is most faithful to the Bible, and its depiction of the way in which God reconciles us to himself.

PSA means that, ultimately, we sinners need to be saved from God’s wrath, which is God’s perfectly justifiable anger toward sin. (I preached on that topic last week.) Notice I say “perfectly justifiable.” I like the way N.T. Wright puts it in this essay:

The biblical doctrine of God’s wrath is rooted in the doctrine of God as the good, wise and loving creator, who hates—yes, hates, and hates implacably—anything that spoils, defaces, distorts or damages his beautiful creation, and in particular anything that does that to his image-bearing creatures. If God does not hate racial prejudice, he is neither good nor loving. If God is not wrathful at child abuse, he is neither good nor loving. If God is not utterly determined to root out from his creation, in an act of proper wrath and judgment, the arrogance that allows people to exploit, bomb, bully and enslave one another, he is neither loving, nor good, nor wise.

But how can we be saved from this wrath?

We need a human representative to endure it for us—one who is himself without sin. Who would be qualified to do that? Only a human being who is also (somehow) God. As St. Anselm of Canterbury put it in the eleventh century, “If it be necessary, therefore… that [salvation] cannot be effected unless the aforesaid satisfaction be made, which none but God can make and none but man ought to make, it is necessary for the God-man to make it.”^[1]

This is, of course, precisely what the God-man, Jesus Christ, has done for us. When Jesus prays in the Garden of Gethsemane, “My Father, if it be possible, let this cup pass from me,” the “cup” is a reference, as in Isaiah 51:17 and 22, and Jeremiah 25:15, to God’s wrath being poured out. PSA means, in a way, that God saves us from God. Because of God’s perfect justice, God requires a payment. Because of God’s perfect love, God makes the payment. This payment, by the way, is what the Bible means, even in last Sunday’s scripture, when it speaks of “propitiation.” PSA does not pit God’s justice against God’s love: on the cross, they are in perfect harmony.

I like the way one commentator, quoted by N.T. Wright in his defense of PSA, puts it in a nineteenth-century commentary:

God is love, say [some], and therefore he does not require a propitiation. God is love, say the Apostles, and therefore he provides a propitiation. Which of these doctrines appeals best to the conscience? Which of them gives reality, and contents, and substance, to the love of God? Is it not the apostolic doctrine? Does not the other cut out and cast away that very thing which made the soul of God’s love to Paul and John? . . . Nobody has any right to borrow the words ‘God is love’ from an apostle, and then to put them in circulation after carefully emptying them of their apostolic import. . . . But this is what they do who appeal to love against propitiation. To take the condemnation out of the Cross is to take the nerve out of the Gospel . . . Its whole virtue, its consistency with God’s character, its aptness to man’s need, its real dimensions as a revelation of love, depend ultimately on this, that mercy comes to us in it through judgment. (James Denney, The Second Epistle to the Corinthians, Expositor’s Bible, Hodder, 1894, p. 221f.)

Notice the last sentence: PSA is “consistent with God’s character.”

The appeal to God’s character answers an objection we may have: If God’s justice demands propitiation (because of our sin) and God’s love offers it (through the death of God’s Son Jesus—who is also God, remember), isn’t this—to put it in human terms—like withdrawing money from one account, which belongs to you, and depositing it another account, which also belongs to you? After this transaction, you’re neither richer nor poorer. So why bother? Why can’t God merely forgive us without the cross?

Because we remember God’s character. God’s law emerges from his very nature. In a sense, then, as Stephen Wellum puts it, God is the law. Therefore all sin—which kindles God’s wrath—is against God.

Since God is the law, he cannot forgive our sin without satisfying his own holy and righteous demand. For God to forgive sin apart from the punishment of our sin or its full satisfaction is impossible. God cannot overlook our sin nor can he relax the retributive demands of his justice because he cannot deny himself. The God of the Bible is a se: self-existent, self-attesting, and self-justifying, which entails that he must punish sin because our sin is against him. Sin is not foremost against an external, impersonal order outside of God; it is against him, the triune-personal God of holy love, righteousness, and justice.^[2]

This helps me.

If we would never expect or want God to do anything to compromise or contradict his love and mercy—which spring from his nature—why should we expect God to do something (or avoid doing something) that compromises or contradicts his justice? His love and justice are both part of who God is.

1. Fleming Rutledge, The Crucifixion: Understanding the Death of Jesus Christ (Grand Rapids: Eerdmans, 2015), 157-8.

2. Stephen Wellum, Christ Alone (Grand Rapids, MI: Zondervan, 2017), 178.