A few years ago, I was asked on camera what I would say to the Pope if I had two minutes with him. I said I would ask him what he believed about justification. The video ended with me putting the question to the Pope and then responding as follows:
“Do you teach that we should rely entirely on the righteousness of Christ imputed to us by faith alone as the ground of God being 100% for us, after which necessary sanctification comes? Do you teach that?”
And if he said, “No, we don’t,” then I’d say, “I think that right at the core of Roman Catholic theology is a heresy,” or something like that.
“Heresy” is a strong word. The problem with it is that its meaning and implications are not clear. Dictionary.com defines heresy, for example, as:
opinion or doctrine at variance with the orthodox or accepted doctrine, especially of a church or religious system.
any belief or theory that is strongly at variance with established beliefs, customs, etc.
You can see how fluid such definitions are.
So what did I mean in the video?
I meant that the rejection of 1) the doctrine of the imputation of the righteousness of Christ as an essential part of the basis of our justification, and 2) the doctrine that good works necessarily follow justification but are not part of its ground — the rejection of those truths is a biblical error so close to the heart of the gospel that, when consistently worked out, will undermine saving faith in the gospel.
The reason for saying, “when consistently worked out,” is because I think it is possible to inconsistently deny the truth of imputation while embracing other aspects of the gospel (blood bought forgiveness, and propitiation, for example), through which God mercifully saves.
I am thankful that God is willing to save us even when our grasp of the gospel may be partial or defective. None of us has a comprehensive or perfect grasp of it.
Nevertheless, God’s mercy is not a warrant to neglect or deny precious truths, especially those that are at the heart of how we get right with God. And the teachers of the church (notably the Pope) will be held more responsible than others for teaching what is fully biblical.
Thus, any church whose teaching rejects the imputation of the righteousness of Christ as an essential ground for our justification would be a church whose error is so close to the heart of the gospel as to be involved in undermining the faith of its members.
More from John Piper on the imputation of Christ’s righteousness: