Alienation is a term philosophers such as Marx and Hegel and later Existential philosophers apply to a wide variety of phenomena, including any feeling of separation from, and discontent with, society; feeling that there is a moral breakdown in society; feelings of powerlessness in the face of the solidity of social institutions; the impersonal, dehumanised nature of large-scale and bureaucratic social organisations. Kierkegaard recognizes and accepts the notion of alienation, although he phrases it and understands it in his own distinctly original terms. For Kierkegaard, the present age is a reflective age—one that values objectivity and thought over action, lip-service to ideals rather than action, discussion over action, publicity and advertising to reality, and fantasy to the real world. For Kierkegaard, the meaning of values has been removed from life, by lack of finding any true and legitimate authority. Instead of falling into any claimed authority, any "literal" sacred book or any other great and lasting voice, self-aware humans must confront an existential uncertainty.
Humanity has lost meaning because the accepted criterion of reality and truth is ambiguous and subjective thought—that which cannot be proven with logic, historical research, or scientific analysis. Humans cannot think our choices in life, we must live them; and even those choices that we often think about become different once life itself enters into the picture. For Kierkegaard, the type of objectivity that a scientist or historian might use misses the point—humans are not motivated and do not find meaning in life through pure objectivity. Instead, they find it through passion, desire, and moral and religious commitment. These phenomena are not objectively provable—nor do they come about through any form of analysis of the external world; they come about through inward reflection, a way of looking at one’s life that evades objective scrutiny.
Kierkegaard's analysis of the present age uses terms that resemble but are not exactly coincident with Hegel and Marx's theory of alienation. However Kierkegaard expressly means that human beings are alienated from God because they are living too much in the world (see Christian existentialism). Individuals need to gain their souls from the world because it actually belongs to God. Kierkegaard has no interest in external battles as Karl Marx does. His concern is about the inner fight for faith.
Luke 14:27 Whoever does not carry his cross and come after me cannot be my disciple. (The Bible) Guidance enough is indeed offered on life's way, and no wonder, since every error passes itself off as guidance. But even though errors are numerous, truths are still only one, and there is only one who is “the Way and the Life,” only one guidance that indeed leads a person through life to life. Thousands upon thousands carry a name by which it is indicated that they have chosen this guidance, that they belong to the Lord Jesus Christ, after whom they call themselves Christians, that they are his bond-servants, whether they be masters or servants, slaves or freeborn, men or women. Christians they call themselves and they also call themselves by other names, and all of them designate the relation to this one guidance. They call themselves believers and thereby signify that they are pilgrims, strangers and aliens in the world. Indeed, a staff in the hand does not identify a pilgrim as definitely as calling oneself a believer publicly testifies that one is on a journey, because faith simply means: What I am seeking is not here, and for that very reason I believe it. Faith expressly signifies the deep, strong, blessed restlessness that drives the believer so that he cannot settle down at rest in this world, and therefore the person who has settled down completely at rest has also ceased to be a believer, because a believer cannot sit still as one sits with a pilgrim's staff in one's hand – a believer travels forward. (Soren Kierkegaard, Upbuilding Discourses in Various Spirits, p. 217-218)
Albert Camus wrote about the idea of being a stranger in the world but reversed Kierkegaard's meaning. A stranger for Camus was someone living in the world who is forced to exist in a Christian way even though the individual does not want to be a Christian. But Kierkegaard was discussing the Christian who wants to be a Christian living in a world that has abandoned Christianity. Both Camus and Kierkegaard had in common an equal distaste for a Christian Democracy where all are forced to take a positive part in Christianity because freedom of choice would be lacking and a non-Christian Democracy where none are allowed to take an active part in Christianity. Kierkegaard put it this way in his Attack Upon Christendom, published 1854-55:
In the New Testament sense, to be a Christian is, in an upward sense, as different from being a man as, in a downward sense, to be a man is different from being a beast. A Christian in the sense of the New Testament, although he stands suffering in the midst of life’s reality, has yet become completely a stranger to this life; in the words of the Scripture and also of the Collects (which still are read-O bloody satire!-by the sort of priests we now have, and in the ears of the sort of Christians that now live) he is a stranger and a pilgrim-just think, for example of the late Bishop Mynster intoning, “We are strangers and pilgrims in this world”! A Christian in the New Testament sense is literally a stranger and a pilgrim, he feels himself a stranger, and everyone involuntarily feels that this man is a stranger to him. (Soren Kierkegaard, Attack Upon Christiendom , The Instant, No. 7)
Recommended books by Søren Kierkegaard (reading list)
Works by Kierkegaard:Fear and Trembling (1843)
Philosophical Fragments (1844)
The Concept of Dread (1844)
Concluding Unscientific Postscript (1846)
Sickness unto Death (1846)
Works of Love (1847)
Christian Discourses (1848)
Training in Christianity (1850)