The idea that God reveals himself to human beings is central in Judaism, Christianity and Islam, but differs in regard of content and conceptualization. The first volume of the new series Key Concepts in Interreligious Discourses points out similarities and differences of "revelation". KCID aims to establish an archeology of religious knowledge in order to create a new conceptual platform of mutual understanding among religious communities. Erratum: Wenzel Maximilian Widenka is co-author of the epilogue (pp. 195-206).