Aware of the fundamental criticism against mysticism in theological literature of this century, this volume radicalizes the tradition of Negative Theology and defines mysticism as the realization of non-duality. Interpreting the term by the religio-philosophy of the modern Japanese Zen-master Hisamatsu Shinichi, an outstanding point of comparison is found to test the Gospel of John for mysticism.The comparison is based on texts from John 13-16, their philological analysis and historical interpretations, but takes place in the hermeneutical reflections confronting systematically Hisamatsus description of the process to Great Awakening with the Johannine path to the eschatological event of Easter-Pentecost.The non-conventional approach is especially important to scholars of the New Testament and Systematical Theology. It is an example of an interreligious dialogue in process that touches and invites further reflections.