S๘ren Aabye Kierkegaard was a Danish philosopher, theologian, poet, social critic, and religious author. He wrote critical texts on organized religion, Christendom, morality, ethics, psychology and philosophy of religion, displaying a fondness for metaphor, irony and parables. He is widely considered to be the first existentialist philosopher.
Much of his philosophical work deals with the issues of how one lives as a "single individual", giving priority to concrete human reality over abstract thinking, and highlighting the importance of personal choice and commitment. He was a fierce critic of idealist intellectuals and philosophers of his time, such as Georg Wilhelm Friedrich Hegel, Johann Wolfgang von Goethe, Friedrich Wilhelm Joseph Schelling and Karl Wilhelm Friedrich Schlegel as well as Danish pastors Jacob Peter Mynster and Hans Lassen Martensen and Danish poet Johan Ludvig Heiberg.
His theological work focuses on Christian ethics, on the institution of the Church, and on the differences between purely objective proofs of Christianity and the individual's subjective relationship to Jesus Christ, the God-Man, which came through faith. Much of his work deals with the art of Christian love. He was extremely critical of the practice of Christianity as a state religion, primarily that of the Church of Denmark. His psychological work explored the emotions and feelings of individuals when faced with life choices. His thinking was influenced by the Bible, Socrates and the Socratic method.