Kierkegaard, Purity of Heart: Do you will only one thing?

What then must I do?
The listener's role in a devotional address

...
The talk asks you, then, or you ask yourself by means of the talk, what kind of life do you live, do you will only one thing, and what is this one thing? The talk does not expect that you will name off any goal that only pretends to be one thing. For it does not intend to address itself to anyone with whom it would not be able to deal seriously, for the reason that such a man has cut himself off from any earnest consideration of the occasion of the address. There is still another reason: a man can, to be sure, have an extremely different, yes, have a precisely opposite opinion from ours, and one can nevertheless deal earnestly with him if one assumes that finally there may be a point of agreement, a unity in some universal human sense, call it what you will. But if he is mad, then one cannot deal with him, for he shies away from just that final point, in which one at last may hope to find agreement with him. One can dispute with a man, dispute to the furthest limit, as long as one assumes, that in the end there is a point in common, an agreement in some universal human sense: in self-respect. But when, in his worldly strivings he sets out like a madman in a desperate attempt to despise himself, and in the face of this is brazen about it and lauds himself for his infamy, then one can undertake no disputing with him. For like a madman, and even more terribly, he shies away from this final thing (self-respect) in which one might at last hope to find agreement with him.

The talk assumes, then, that you will the Good and asks you now, what kind of life you live, whether or not you truthfully will only one thing. It does not ask inquisitively about your calling in life, about the number of workers you employ, or about how many you have under you in your office, or if you happen to be in the service of the state. No, the talk is not inquisitive. It asks you above all else, it asks you first and foremost, whether you really live in such a way that you are capable of answering that question, in such a way that the question truthfully exists for you. Because in order to be able earnestly to answer that serious question, a man must already have made a choice in life, he must have chosen the invisible, chosen that which is within. He must have lived so that he has hours and times in which he collects his mind, so that his life can win the transparency that is a condition for being able to put the question to himself and for being able to answer it -- if, of course, it is legitimate to demand that a man shall know whereof he speaks. To put such a question to the man that is so busy in his earthly work, and outside of this in joining the crowd in its noisemaking, would be folly that would lead only to fresh folly -- through the answer.

(Soren Kierkegaard, Purity of Heart Is To Will One Thing, trans. by Douglas V. Steere (Harper & Row, 1965), pp. 183-184.)