Robert Jenson on good works
Most ethical theories and all sensible persons have known that a good act cannot appropriately be done for an ulterior egocentric reason. If I feed my hungry neighbor in order that I may acquire stars for my crown, I thereby lose the claim to any stars. But the mere injunction, “Do good to your neighbor for his sake, not for yours,” does not itself make a way out of our egocentric predicament. If, in order that I shall not be egocentric and so lose the value of my deed, I try to act purely for my neighbor, this is only a new egocentricity. The radically proclaimed gospel frees me from moral egocentricity in that it does not merely tell me I ought not try to get anything out of my act for my neighbor, but that I cannot get anything out of it, that I will not in fact be rewarded at all. Only the word, “You have nothing whatever to gain from your efforts on behalf of your neighbor’s belly,” frees me to attend to his belly. To the question, “Why should I do good?” the radical gospel replies, “If you put it that way, no reason.” Just so the radical gospel frees me to do good in the only way in which good can – by the unanimous testimony of human wisdom – be consistently done at all. […]
Thus the doctrine of justification by faith effects a particular secularization of morality. On my side, the chain of reasons cannot reach past the temporal consequences of the act into eternity or the eschaton. If I feed my neighbor in order to gain a vote for my party, there is nothing the matter with that, if it is legal. And I can go on: in order to bring my party to power, in order to enact my party’s social-welfare program, and so on – but if the gospel is true, the chain can never legitimately reach to any supernatural or eschatological reasons. On the neighbor’s side, there is no restriction. My reasons may well extend into the eschaton: “Whyshould I feed my neighbor?” “In order that his belly may be filled.” “Why should his belly be filled?” “To make a sound body for god’s resurrection!” […]
A believer, we may say, is someone who knows he does not need to care for himself, since God will do that, and so has all that time and energy left to care for other people.
from Lutheranism: The Theological Movement and Its Confessional Writings, (Fortress, 1976), 146, 147, 152.