According to Peter Eicher's standard monograph on this topic, the concept of self-revelation is to be considered the 'Principle of Modern Theology'. Despite profound differences in approach and development, this basic concept is shared by the most heterogeneous modern theologians, such as Karl Barth, Emil Brunner, Rudolf Bultmann, Hans Urs von Balthasar, Karl Rahner, Richard Niebuhr, Jürgen Moltmann, Eberhard Jüngel and Wolfhart Pannenberg . A more or less balanced composition of their different approaches is part of every undergraduate introduction to contemporary theology, as articulated, for example, in the Christian theology of Alasdair McGrath: “God took the initiative through a process of self-revelation, which achieves its culmination and fulfillment in the story of Jesus of Nazareth”. However, despite the modern penchant for projecting the concept of self-revelation onto decontextualized Bible verses such as John 14:9, self-revelation is anything but biblical in origin. Despite this, only a few scholars are aware of how modern theology came to adopt this concept; is adopted somewhat unreflectively. This is ironic, particularly in the context of modern biblical studies. Eicher's 1977 monograph on this topic identifies two fundamental characteristics of self-revelation that have characterized the more or less unreflective appropriation of this concept in the last century:1. The unity of the revelatory subject and the revealed content of revelation: self-revelation does not concern a revealed book, as in Islam, nor a deposit of revealed sentences about "objects of faith" (e.g. the Trinity, the Incarnation, the sacraments), as in neo-scholasticism. Rather it is based on God's “self-revelation” in the “personal enclosure… at the center of the paper… pistemological break between premodernity and modernity as follows: Seen from the premodern point of view of Cusa, Descartes's proceedings arouse suspicion of idolatry. Modern rationalism attributes to a definable (and consequently finite) theological concept "that which suits only reality itself". Seen from the rationalist Cartesian point of view, Cusa's procedure raises the suspicion of irrationalism: his wisdom of unknowing allows an "excess" of worship, that is, the adoration of a reality that offends and surpasses the principles of human rationality in promote an insatiable and erotic desire for the infinite. It is possible to show that Descartes' narrow concept of rationality is logically flawed, but this is not relevant here. Rather, I will focus on the impact of this concept of rationality on the birth of modern theology of revelation.