5. Prove that penal substitution is the only theory of Jesus’ death which makes sense. There is nothing new under the sun. In 1888, William Blaikie was combating the same problems we face today. Here is what he had to say about the denial of the atonement:
If the death of Jesus Christ on the cross was not demanded as a sacrifice for
sin, it was a crowning instance of the miscarriage of justice. People talk
of the immorality of the atonement; punishment they say is for the guilty, and
rewards only for the righteous: you never can be justified in punishing the
innocent and acquitting the guilty. Yet according to their view, the best
of all the human race suffered a shameful and cruel death, was the victim of the
most miserable injustice; and this fact, instead of horrifying men, is expected
to impress them above everything else with respect for the government of God,—it is to make such an impression on them as will rectify all the disorders of their
moral nature. Would it not have been infinitely better, if the purpose of
Jesus Christ in visiting our world was merely to afford a pattern for
self-sacrifice, that he should have lived through the whole term of human life,
exemplifying at its every stage the spirit of self-denying love, and showing how
even to hoar [gray] hairs life might be made beautiful by a pure devotion to
duty, and diffuse to its very close the fragrance of myrrh and aloes of
cassia? Why cut short a life before it was well begun that might have been
so useful? The truth is, the Cross of Christ is an utter mystery—is more
than a mystery—without the atonement.
To put that into my words…If God sent Jesus to die merely to teach us how to love; to show His triumph over Satan; and to inspire us to follow hard after God—(I say it reverently) that might be considered cruel. Because He could have done all these things without dying in blood and agony! If Jesus died for any lesser purpose than to bridge the gap between a holy God and sinful mankind; to pay the penalty that our sins deserve; to open heaven’s door to the undeserving—(I say it reverently) that might be considered a cosmic injustice!
Yes, Jesus’ death did accomplish a variety things. But the main thing it accomplished was the sacrificial payment of the full debt incurred by our sins. In fact, that accomplishment provides the foundation for all the other achievements of the cross! For the cross teaches us to love sacrificially precisely because it was an act of sacrificial love itself. The cross inspires us to follow Christ because He accomplished something incomparable in His death. And the cross shows forth Christ’s victory over Satan because, at the cross, Satan’s chief accomplishment (bringing sin into the world) is undermined! For all these reasons, the cross simply has to be primarily about penal substitution.
So, thank God that Jesus died in our place! Thank God that He “so loved the world that He gave His only begotten Son.” Thank God that “He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him.” That God that Jesus willingly laid down His life for the sheep. For “without the shedding of blood” (Hebrews 9.22), “there is no forgiveness.”