The foreigner or the union in the difference stands out in the whole of Michel de Certeau's work due to the breadth of the public to which it is directed, the intensity with which it reflects the vital experience of its author and its condition as a hinge between two very different from their trajectory. It could be defined as a spiritual text, born directly from Certeau's religious experience, in which he unfolds his vision of some of the problems that he considered central in his attempt to live as a Christian, including also the proposals for him to face them.
Among these themes, the most insistent, the one most dear to the author probably concerns what he calls the need to travel, that trip outside the country of his parents that is required of Abraham by Yahweh in the biblical account. Each one goes towards that encounter with the other that, altering him, reveals the fragility of his evidences in the movement of «common life» and from the acute awareness that «God continues to be a foreigner for us».
The Stranger is Certeau's most personal and profound book, with which he offers his readers two gifts at the same time: the faithful testimony of a past time and the discovery of the validity that the Christian heritage continues to preserve, although it requires the construction of a new language in order to bring it to light. First published in 1969, this book was a retrospective look for its author. A look at a world —Christian— in which he had lived, but which was disappearing in plain sight.