The following is a reflection by Gerhard O. Forde on Martin Luther’s Heidelberg Disputation, and what it looks like to be a theologian of the cross versus a theologian of glory.
Thesis 22. That wisdom which perceives the invisible things of God by thinking in terms of works completely puffs up, blinds, and hardens.
Thesis 22 is, in effect, a statement about the religious effect of the theology of glory and the wisdom of law upon which it is based. Religious people in particular seem to have difficulty being theologians of the cross. That is because the theology of the cross is quite devastating for our usual religious aspirations under the wisdom of law. The indignation and resentment against God … is aroused not only — perhaps not even principally! — because of the strenuousness and rigor of the life proposed, but finally because in the cross God has literally taken away from us the possibility of doing anything of religious merit. In Jesus God has cut off all such possibility. God, as St. Paul could put it, has made foolish the wisdom of the wise. We are rendered passive over against God’s action. This is always galling for the old being. We adopt a very pious posture. It is, so the protests go, too easy, too cheap, it has no obvious ethical payoff, and so on and on. Religiously we like to look on ourselves as potential spiritual athletes desperately trying to make God’s team, having perhaps just a little problem or two with the training rules. We have a thirst for glory. We feel a certain uneasiness of conscience or even resentment within when the categorical totality of the action of God begins to dawn on us. We are always tempted to return to the safety and assurance of doing something anyway. Generally, it is to be suspected, that is all we planned to do, a little something. But to surrender the “wisdom” of law and works, or better, to have it taken away, is the first indication of what it means to be crucified with Christ. (Gerhard O. Forde, “On Being a Theologian of the Cross: Reflections on Luther’s Heidelberg Disputation, 1518,” 91-93)