Penal Substitutionary Atonement

Why did Jesus die?

Charles Simeon is someone I’ve grown fond of through various biographies - he was a remarkable English pastor who lived in 18th Century Cambridge. Writing about his own conversion, Simeon mentions that of all the books of the Bible that might have sealed his remarkable transformation, it wasn’t any of the gospels, and it wasn’t Romans or Ephesians. The book that did it was the Old Testament book of Leviticus.

He describes reading about the penitent man laying his hands on an animal without blemish, and then seeing the animal slain and its blood sprinkled around the altar. That image absolutely gripped Simeon. Reading a commentary on Leviticus, one sentence in particular struck him deeply: “The Jews knew what they did when they transferred their sin to the head of their offering.”

The “transfer of sin” that is being described here is the essence of “penal substitutionary atonement”. The idea that in order for our sin to be dealt with, someone must - as our substitute - take the penalty our sin deserves.

The fact that we all die is not accidental. As Genesis chapter 3 makes clear, we die because the penalty for our sin is death. So the only way to deal with death is to deal with our sin.

The entire sacrificial system of the Old Testament was put in place so that God’s people would understand this. God commanded that animal sacrifices be made as a way of showing that sin must be paid for. As they laid hands on an animal, they were symbolically transferring their sin onto the animal, which then died in their place. This is what Simeon was reading about in Leviticus.

The principle is played out dramatically in Exodus 12 at the Passover: An unblemished lamb is slain, its blood daubed around the doorway of each household. The people in the household would eat the lamb, to show their identification with it. And as a result, that family was spared. Because the lamb died, they lived.

However, as it says in Hebrews chapter 10, “it is impossible for the blood of bulls and goats to take away sins”. The death of an animal cannot atone for the sin of a human being. So the animal sacrifices of the old covenant were merely intended to point forward, toward a greater sacrifice that God would one day provide.

This “greater sacrifice” is described in Isaiah chapter 53, where we read of a man who bears the penalty for the sins of others, so that they would not have to:

...he was pierced for our transgressions; he was crushed for our iniquities; upon him was the chastisement that brought us peace, and with his wounds we are healed. All we like sheep have gone astray; we have turned—every one—to his own way; and the LORD has laid on him the iniquity of us all.

Who is this person Isaiah speaks of?

As Hebrews chapter 9 confirms, Jesus Christ is the one to whom Isaiah looked forward. In his death, Jesus “put away sin by the sacrifice of himself”.

Hebrews, as well as the book of Romans and First John, all describe Jesus’ death in substitutionary terms. They argue that Jesus’ death on the cross was a “propitiation”, satisfying the righteous wrath of God by bearing the punishment that we deserve. Similarly, in Galatians, Paul says that “Christ redeemed us from the curse of the law by becoming a curse for us”. Peter, in a self-conscious echoing of Isaiah 53, also writes about that same substitutionary atonement: “[Christ] himself bore our sins in his body... that we might die to sin and live to righteousness. By his wounds you have been healed.”

The substitutionary nature of Jesus’ atonement has been contested by some theologians. And yet it is all over the pages of Scripture. Not in isolated verses, but woven deeply into the fabric of the entire sacrificial system of the old covenant. And then affirmed, as we’ve seen, by the New Testament authors.

The idea of the hero willingly giving up his life to save those he loves is written everywhere, not just in the pages of Scripture. Think of Boromir in the Lord of the Rings, Tony Stark in Avengers: Endgame, Obi-Wan Kenobi in Star Wars. Or my favourite, The Iron Giant, saving people from destruction - even people who are trying to destroy him - by deliberately putting himself between them and a nuclear warhead. He dies so they can live.

The idea of substitutionary atonement is everywhere. I believe it’s because as creatures made in God’s image, struggling with guilt and shame, and facing the inevitability of death, we know that we need saving. But we also sense that it cannot be done cheaply or easily. Our predicament is too severe, too desperate. Our sin too serious. Death cannot simply be waved away.

So who can defeat death for us? To do that, someone would need to deal with our sin. And only one person in history is qualified to take our sin on Himself, given that He had no sin of His own to die for. The unblemished Lamb of God, who takes away the sin of the world.

The One who turned to his friends shortly before he died and said to them: “Greater love has no one than this, that someone lay down his life for his friends.”