It is generally claimed that penal substitution and participatory models of atonement are compatible as complementary, alternative perspectives on atonement, and that the debate primarily concerns their relative priority: which view is over-arching and which is subordinate. It seems to me, however, that there is a fundamental inconsistency between the two models. If substitution means a strict “instead-of” replacement, then it would seem to preclude a participatory communion or fellowship. If Christ died instead of us, then how is it that we unite with Him in death? Furthermore, in what sense did He die, but we do not also die? He died a bodily death because of taking on our sins. But each of us also dies a physical, bodily death because of our sins. In our spiritual union with Him, by faith, He took our sins upon Himself, not as a removal of sins, but as a sharing of sins. The sins are then subsequently removed, i.e. condemned and destroyed, in both His bodily death and in our own bodily death, as we are united in death. The second part of the “sweet exchange” (2 Corinthians 5:21) is that His righteousness is shared with us: the life-giving, cleansing power of His blood, resulting in our resurrection with Him. There is therefore no spiritual death, either for Christ or for us who are in Him. As it was for the repentant thief, we pass from death to be with Him in paradise, to await resurrection. All of this is a matter of participatory sharing, not of “substitution”. It is a union with Him that begins at the cross, continues in paradise, and is carried through into the resurrection and new creation. There is no point throughout this fellowship where He experiences something without us, nor where we experience something without Him.
How does this relate to OT sacrifices? To regard any of them as penal-substitutionary (a death instead-of, as punishment for sin) is also a misunderstanding. The animals slain for atonement and for sin were not regarded as bearing the peoples’ sins. To the contrary, they were holy and unblemished. Their blood was a source of life, with power to purify, to cleanse, to sanctify, to make acceptable for God’s presence. Similarly, the Passover lamb was slain, not to receive punishment for sin, but to provide the blood that would protect against death. It was the life-giving blood that sanctifies, so that the Lord could be present, and thus deliver them from death. The only animal upon which sins were bestowed was the scapegoat, which was driven away from the camp, unsuitable as a sacrifice. The only sacrifice that was “substitutionary” was the redemption of the firstborn. But that had nothing to do with sin. It was an acknowledgement that the firstborn belongs to God, and a sign that all Israel, as God’s firstborn, belongs to Him. All these offerings point to Christ for their fulfillment, representing several aspects of what He accomplished on the cross. But none of them entail penal substitution.
In the texts used to defend the substitution model, which speak of His dying for us or for our sins, the word “for” is a translation of hyper (e.g. John 10:11; Romans 5:8) or peri (as in Romans 8:3-4; 1 Thess 5:10; 1 John 2:2). Both prepositions would have the meaning of “on behalf of” or “for the sake of” in these contexts. The idea of a substitutionary “instead-of” is a possible interpretation, but is by no means required. All these texts could just as well be interpreted as “on behalf of, by virtue of participatory fellowship”. Similarly, the texts in Isaiah 53 (53:4-6, 8, 10-12) do not require a substitutionary interpretation, but can be understood as sharing our sins, griefs and punishment. Note Isaiah 53:12 – “[He] was numbered with the transgressors; yet He Himself bore the sin of many, and interceded for the transgressors.” The transgressors, with whom He was numbered, were not just the adjacent crucified thieves; they were the “many” for whom He bore sins and interceded. This indicates participatory fellowship, not substitution. One might also consider John 11:50, where Caiaphas declares that one man should die instead of the nation. There are two reasons why this is not directly applicable to penal-substitution: 1) it is reasoned as a matter of political expediency, not punishment for sin; 2) it pertains to the death of the nation, corporately, rather than to the death of individuals.
In view of all the texts that explicitly and definitively teach participation, that must be the model of choice, rather than penal substitution.