G.B. Caird on (Sin)cerity

While reading George Caird's masterful New Testament Theology, he brings to the fore an interesting and often overlooked aspect of the types of sins Jesus died for, namely, the sin of sincerity.

Caird states:

If it be true that Jesus died for such as Paul, then the one thing certain is that the sins he bore included the sins of sincerity. ...Christian tradition has regrettably accustomed us to think of those who brought about the Crucifixion as villians; but if we observe them through the eyes of Paul, we get a different view. 'I bear them witness that they have a zeal for God, however unenlightened' (Rom. 10:2). No doubt they had their faults and fallacies, but each in his own way was a sincere person, honestly trying to do what was right in the interest of religion and national survival. But in all the annals of human vice, no power is as destructive or demonic as perverted sincerity.

It took the Cross, interpreted as the vicarious bearing of guilt to pierce the armour-plate of Paul's self-congratulation. It proved that when he had been most confident of serving God, he had been God's enemy; and it had revealed a love great enough to kill the enmity (Rom. 5:8; 2 Cor. 5:18-21) (Italics mine; 147).