Penal Substitution and Atonement in General
"Atonement theories confirm two fundamental and universal instincts about life and divinity: the belief that nothing is free, that there must be give-and-take in the spiritual economy as there is in the material; and secondly, the intuition that ritual establishes order... The problem is not what all this says about Jesus but what it says about God: if God wants to save, why is such intercession necessary? Why should Jesus' pleading for humanity only be effective after he had been murdered? It does us no good to perceive Jesus as heroic if we are forced to view God as sadistic." (Stephen Finlan, Problems with Atonement, pp 80,97)The idea of penal substitution is peripheral to the New Testament. Two books which should be required reading for the origins of atonement doctrine are Stephen Finlan's The Background and Content of Paul's Cultic Atonement Metaphors and its sequel Problems with Atonement. Finlan distinguishes between four understandings of Christ's death found in the New Testament: martyrdom, sacrifice, scapegoat, and ransom redemption. None of these really involves the idea of penal substitution where Christ supposedly "stands in" for others.
1. Martyrdom. Christ dies as an example to be followed (Gal 2:19; Rom 6:6-7,11; I Pet 2:21,4:1-2).
(a). Passover Sacrifice. Christ dies in order to protect believers from God's wrath in judgment (I Cor 5:7,11:23-26; I Pet 1:19; Mk 14:22-25/Mt 26:26-29/Lk 22:14-20).
(b). Covenant Sacrifice. Christ dies in order to make peace between people and renew commitment to God (Gal 3:14; I Cor 11:25; Mk 14:24/Mt 26:28/Lk 22:20; Heb 7:22,8:6,9:15-21).
(c). Atoning Sacrifice. Christ dies in order to reconcile humanity to God through forgiveness (Rom 3:25; Mt 26:28; Eph 1:7; I Jn 2:2,4:10; Heb 2:17,9:11-14,22,26,10:10,19).
3. Scapegoat. Christ dies taking on curses and bearing away peoples' sins (Gal 3:13; II Cor 5:21; Rom 6:6,7:4,8:3; I Pet 2:23-24; Heb 9:28).
4. Ransom Redemption. Christ dies as the price for humanity's freedom, liberating people from captivity under evil (Gal 3:13; Rom 3:24; I Cor 6:20,7:23; Eph 1:7; I Pet 1:18; Mk 10:45/Mt 20:28; I Tim 2:6; Tit 2:14; Heb 2:14-15,9:12,15).
Neither martyrs (1) nor scapegoats (3) were substitutes. The former were examples to be followed, and the latter were sin carriers. Scapegoats were not sacrifices, a point emphasized repeatedly by Finlan. They were opposite in every way: sacrifices pure and offered to God, scapegoats impure and driven out to a demon.
Sacrifices (2) involved substitution, though not in a penal sense. A sacrifice didn't "stand in" for the offender, but appeased God's wrath in a propitiary sense. It was a monetary substitution (or "food bribe"), buying off God more than anything, and closer to the satisfaction model introduced in the 11th century, based as it was on honor-shame values. Moreover, the propitiary aspect of sacrifice is only half the picture: a sacrifice was also expiatory, in the sense that blood was a cleansing agent on its own right. The expiatory dimension to sacrifice wasn't about any kind of substitution, let alone penal.
Ransom redemption (4) involved substitution, though as a monetary transaction; it had nothing to do with penal substitution.
The only passage in the New Testament which possibly evokes penal substitution is I Pet 2:24b (cited by Michael), which owes to Isa 53:4-5, "by his wounds we are healed". This may indicate that Christ, like Israel's servant, died in place of others. Aside from this one text, however, there is nothing in the NT pointing to Christ's death as a penal substitute.
The lesson here is that the NT writers used and blended many metaphors of Christ's death so that "any one metaphor, by itself, would be misleading" (Finlan, Problems with Atonement, p 66). If there is a prime metaphor, it's martyrdom, which provides the platform for the others. But from the second century onward, church thinkers started to use a single atonement metaphor under which other ideas were subordinated. These were ransom redemption (the "Orthodox" view), satisfaction (the "Catholic" view), and penal substitution (the "Protestant" view). Each understanding moved further away from the biblical metaphors:
1. Ransom Redemption. God tricks the devil by offering Jesus as a ransom payment to free humanity from his influence, and Satan is foiled by the resurrection. (Origen, Augustine, Gregory the Great; dominant theory in the 2nd-10th centuries)
2. Satisfaction. Christ dies in the place of humanity, in order to satisfy the demands of God's honor. (Anselm; dominant theory in the 11th-15th centuries)
3. Penal Substitution. Christ dies in the place of humanity, in order to satisfy the demands of God's justice. (Luther, Calvin; dominant from the 16th century onwards)
The ransom redemption theory is based on NT understanding (#4 above), though it introduces deceit into the picture. The satisfaction theory is an honor-shame understanding (reflecting the feudal structure of medieval times) and thus has affinities with the biblical view of sacrifice. The penal substitution theory is the most popular today, but least biblical, as it answers individualist concerns about guilt and innocence.
Whatever its theological merits, I see almost no biblical basis for the penal substitution model. And I'm not sure it's superior to the other two in any case. They get at the same idea, just under the trappings of different value systems.
Is Atonement essential to Christianity?
According to Finlan, the Incarnation is the central doctrine of Christianity, but atonement is something Christianity can (and should) do without. In place of atonement -- and anything relating to blood sacrifice -- he suggests the principle of theosis, whereby "the Word became man so that you might learn from man how man may become God" (Problems with Atonement, p 121). Not that Finlan advocates gnosticism -- far from it: "Those who teach that every person is as divine as Christ is (such as the gnostic gospel of Philip) lose sight of the Incarnation, and cannot really be called Christian" (ibid, p 4; my emphasis). He advocates what orthodox thinkers like Athanasius and Clement of Alexandria maintained, that people may be deified on account of the "the Word becoming man". Says Finlan further:
"Theosis has a biblical basis, and this should not be forgotten. There is the promise that 'you may become participants of the divine nature' (II Pet 1:4); there is the command to become perfect, Godlike (Mt 5:48); there are the prophecies of doing greater things than Jesus did (Jn 14:12) and of revelations yet to be seen (Jn 1:51). Theosis means each person incarnating divinity in his or her small way, inspired by the direct Incarnation of divinity that took place in Galilee and Judea." (pp 121-122)As a Unitarian I'm hardly qualified to say whether or not dispensing with atonement theories amounts to a betrayal of Christianity. But the principle underlying theosis is one I can certainly endorse. To forgive freely -- truly freely, without any give-and-take in between -- is one of the hardest things to do, and divine indeed.