The logic of penal substitution
There are three principal ways in which Christ’s death has been understood in the church:-
First, there is the type of account which sees the cross as having its effects purely on us: it reveals God’s love to us; it tells us how much God hates sin; it sets us a supreme example of godliness; it blazes a trail to God, which we may now follow. The cross motivates us to seek God and it opens up the flow of divine life. This type of view leaves little room for substitution, since it equates what Christ did for us with what he does to us.
Second, there is the type of account which sees the cross as having its effects on the hostile forces around us and arrayed against us. These forces may be seen variously as sin and death, Satan and his minions, or the demonic in society and its structures. We are in thrall to these evil forces, but in the cross God does battle with these forces, and vanquishes them. We are no longer in bondage to them, but share in Christ’s victory over them. Within the view, Christ may properly be regarded as our representative and substitute.
Third, there is the type of account that denies nothing offered by the first two accounts, but adds to them. It asserts that beyond our lack of motivation to love and serve God; beyond the evil forces that are arrayed against us, is a sinful nature within our own hearts that renders us liable to God’s judgment. On this view, Christ’s death had an effect on God, who hereby propitiated himself. Only then did the cross become the means of overthrowing the evil that is external to ourselves, and only then did it reveal God’s seeking and saving love. The cross provides that satisfaction for sins which God’s own character requires. Thus God’s ‘no’ towards us is turned into a ‘yes’.
It should be noted that although the first two views often set themselves in opposition to the third, this third view does in fact include all the positive assertions made by the first two.
It should be noted further that in the foregoing analysis the resurrection has not been mentioned. It is often assumed that the resurrection is part and parcel of the second view, but that on the third view the resurrection is less significant – perhaps even unnecessary. But, in fact, the resurrection is essential to the third view, becuase it is only a living Saviour who can dispense the blessings that his death has secured. Moreover, we should, as previously stated, view these three ways of viewing the cross and complementary, and we should be ready to synthesise them, just as Paul does in Colossians 2:13-15.
Summarising part of J.I. Packer’s lecture ‘What did the Cross Achieve: the Logic of Penal Substitution’. Collected Shorter Writings, 85-123.