Critics of penal substitution or vicarious atonement say it's impossible and/or immoral. I've discussed this objection on several occasions. Now I'd like to approach it from a different angle.
What is atonement? What is redemption? One way to unpack the concept is in terms of making amends for wrongdoing. Do critics of penal substitution/vicarious atonement think it's ever possible (or generally possible) to make amends? Or does their position on penal substitution/vicarious atonement rule that out in principle?
In some case, making amends is fairly straightforward. Suppose I steal your bike. I can make amends by giving it back. Or maybe I buy you a new bike.
But there are types of wrongdoing where it isn't that simple. Suppose I get drunk, get behind the wheel, and run over a pedestrian. I can't give him his life back. I can't restore him to his parents, friends, or siblings. I can't make it up to him or them.
Suppose you steal my girlfriend in college. I retaliate my framing you for a crime. You spend the next 20 years behind bars. Maybe I come to regret my actions. But I can't give you back the lost years. Life is short. Moreover, that was the prime of life. As you age, you have fewer opportunities.
Or suppose I make someone blind by a blow to the head. I didn't intend to blind him. But I can't restore his eyesight. And that's a huge loss.
Sometimes it's less about the quality than quantity. Cumulative regrets. All the things I wish I'd said and done differently. "If I knew then what I know now…" Hindsight can be a curse if it's too late for make it right. All the little things add up. Individually, they may not be irredeemable, but collectively, I can't make amends for the totality.
Two things follow from this:
i) If making amends is possible at all, then it many cases it will have to be a different kind of compensation or restitution than the original wrong. I can't do anything directly analogous to make up for the offense. It must be qualitatively different.
ii) Relatedly, I can't make amends (in cases like that). I can't go back and time and fix it.
If it's possible to make amends at this stage, then someone else will have to do that on my behalf.
But if, apropos (i), that's a different kind of thing than the original, then there's no reason a second party couldn't do so on my behalf. If I can't give you the same kind of thing in exchange for the original offense, if that's unrepeatable, and if, despite that fact, it's possible to make amends by something different, then what does it matter who does it? The connection has already been severed between the original offense and the compensation. It's not like me going back in time to avoid the original offense. I can't change the past in my own person. Indeed, the past is immutable. So there's already going to be some essential discontinuity between the original offense and making amends. It's can't be the same.
A critic could deny this conclusion by saying it's never, or rarely, possible to make amends. Guilt just keeps piling up. You never put it behind you. If so, that's a high price to pay to deny penal substitution or vicarious atonement.