As a theology professor, I routinely hear people claim that Anselm invented the penal substitution view of the atonement. This is the idea that Jesus bore the punishment that we rightly deserved because of our sin, and that this was necessary for us to be reconciled to God.
Before Anselm, the church had a view that focused almost exclusively on ideas like victory—i.e. on the cross Jesus defeated the enemies of humanity like Satan, death, and sin—and healing—i.e. the entirety of his incarnate life healed our broken humanity and made it possible for us to resume the path to godlikeness. (If you’d like some examples, see here and here .)
And people often use the relative newness of the theory as a reason for rejecting it. If the early church didn’t think of the cross as some kind of vicarious punishment, if that was just a medieval invention, let’s get rid of it.
There’s just one problem with this: it’s wrong. And it’s wrong for two important reasons.