Hugely complex topic!
Several theories have been advanced to explain what happened on Calvary, all of them using the language of “payment” in describing the sacrifice. The “ransom” theory, see Matt. 20:28/Mark 10:45, suggests that by sinning mankind became Satan’s captives, and Christ gave himself as a ransom to redeem mankind from Satan’s dominion, resulting in what Rom. 6:16 characterizes as a change of masters. Origen, Augustine and Gregory of Nyssa all championed this theory. (Augustine added some conjecture on why Satan would ever make that deal – one of the starker examples of his often questionable logic.) In contrast, the “restitutional” or “penal substitution” theory, initially developed by Anselm and refined by Calvin, is far more prevalent today. It holds that Christ paid the penalty for mankind’s sin―a death penalty imposed by God since the Fall of Adam and Eve (Gen. 2:17)―and thereby satisfied the legitimate demands of God’s justice. (Aulén’s Christus Victor argues that the early Church Fathers did not hold to the ransom theory as a payment to Satan, but as a ransom from the bondage of sin in general.)
If we are to go with the ransom theory and need to decide to whom the ransom was paid, I suppose we should begin by rounding up OT antecedents. The usual suspect is Is. 53. But 4 Macc. 6:28-29 and 2 Macc. 7:37-38 must also be considered, suggesting that God’s wrath against Israel may be assuaged by the martyrs’ death as representatives of Israel.
One modification is to think of Christ as our champion in a cosmic battle against the Forces of Evil, our representative (the way David was Israel’s representative when he fought Goliath) -- but unlike with David vs. Goliath, Christ’s victory consisted not in surviving the battle and slewing the enemy, but in dying in battle and robbing the enemy of its victory. Once Champion Christ died, we don’t have to; the Evil One has no choice but to accept Christ’s death as the final outcome, as the end game (just as the Philistines took Goliath’s death as the end game) – and retreat. Therein lies both the “substitution” and the “atonement.” Meanwhile, forgiveness doesn’t enter into it per se. Atonement isn’t forgiveness, but a declaration of vicarious victory in the cosmic battle.
Paul’s letters present Christ’s death as representative rather than substitutional (precisely what we would expect from a rabbi steeped in the sacrificial tradition of Israel). 2 Cor. 5:14’s “one has died for all, therefore all have died” (as opposed to “therefore all did not need to die”) suggests this view. Rom. 8:3’s “sending his own Son in the likeness of sinful flesh and for sin, condemned sin in the flesh, in order that the just requirement of the law might be fulfilled in us (as opposed to “might be fulfilled for us”) who walk not by the flesh but by the spirit” suggests it. Gal. 2:20’s “I am crucified with Christ” (as opposed to “Christ is crucified in my stead”) suggests it.
I have no doubt that when Paul wrote “For I delivered to you first of all what I myself received, that Christ died for our sins in accordance with the scriptures” (1 Cor. 15:3), he was relating the teachings of Christ then in currency. Similar teachings were eventually recorded in Matt. 20:28 and Mark 10:45: “The Son of Man came not to be served but to serve, and to give his life as a ransom for many” – but the gospels’ use of the preposition ἀντὶ (translated as “for”) has the connotation “instead of.” By contrast, 1 Cor. 15:3 uses ὑπὲρ (also translated as “for”) – which has the connotation “on behalf of.” Even 1 Tim. 2:6, the only other instance of a “ransom” analogy anywhere in Paul’s letters, uses ὑπὲρ. Never once does Paul use ἀντὶ.
The subtle difference between substitutional atonement (“Christ took my place, so I didn’t have to die”) and representational atonement (“Christ died, and I died with him”) does not get us all the way home. But it’s a start.
